Contact Us    Contact Us     |     Feedback
MOBILE VIEW  | 

ANTS

Export To Excel

Classification   |    Detailed evidence-based information

Substances Included Synonyms

Therapeutic Toxic Class

    A) Ants are insects of the superfamily Formicidae, order Hymenoptera, class Insecta. Ants may have stingers, which may be functional or functionless depending upon the species, or may bite with their mandibles and spray a toxic substance into the wound created by their jaws.
    B) FIRE ANTS
    1) The fire ants species were introduced into the United States near Mobile, Alabama about 1920. They remained in this area until about 1950 when they spread into neighboring states (Triplett, 1973).
    2) There are also several varieties of fire ants in the United States, many of which have been almost eradicated by S. invicta.
    3) The fire ant sting attack rate in endemic areas during the spring and summer is estimated to be 28% to 58% (Stafford et al, 1989a).
    4) It is estimated that in urban infested areas about 30% to 60% of the population is stung each year and that 17% to 56% of those stung will have a large local reaction (Anon, 1990).
    5) In one study of 211 stings in 95 patients, only 2 were severe (1%), 26 were moderate (12%), and 183 (87%) were mild. None required medical care (Stablein & Lockey, 1987).

Specific Substances

    A) CONSTITUENTS OF THE GROUP
    1) Ant
    2) Bullet ants
    3) Dinoponera
    4) Dinoponera australis
    5) Dinoponera gigantea
    6) Dinoponera grandis
    7) Fire ants
    8) Formica exsectoides (Allegheny mound ant)
    9) Iridomyrmex humilis (Argentine ant)
    10) Myrmecia forficata (inchman ant)
    11) Myrmecia pilosula (Jack Jumper ants)
    12) Myrmecia pyriformis
    13) Myrmica gulosa (Red Bull ant)
    14) Paraponera
    15) Pogonomyrex badius
    16) Pogonomyrex barbatus
    17) Pogonomyrex californicus (Red harvester ant)
    18) Pogonomyrex maricopa (Yellow harvester ant)
    19) Pogonomyrex occidentalis
    20) Pogonomyrex rugosus (Black harvester ant)
    21) Pogonomyrmex badius
    22) Pogonomyrmex barbatus
    23) Pogonomyrmex californicus (Red harvester ant)
    24) Pogonomyrmex maricopa (Yellow harvester ant)
    25) Pogonomyrmex occidentalis
    26) Pogonomyrmex rugosus (Black harvester ant)
    27) Ponerinae
    28) Solenopsis aurea (US desert fire ant)
    29) Solenopsis geminata (United States fire ant)
    30) Solenopsis invicta (Imported red fire ant)
    31) Solenopsis richteri (Imported black fire ant)
    32) Solenopsis saevissima (Imported fire ant)
    33) Solenopsis xyloni (United States Southern fire ant)
    34) Tocandiras (Bullet ants)
    35) True Tocandira
    36) False Tocandira

Available Forms Sources

    A) SOURCES
    1) Ants are found virtually throughout the world. Fire ants are native to both North and South America.
    2) Because of predation, Solenopsis invicta (Brazilian fire ant) has almost eradicated native US ant species, the southern fire ant (S. xyloni), the tropical fire ant (S. geminata), and the black fire ant (S. richteri) (Stafford et al, 1989a).
    B) USES
    1) Various venomous alkaloids have been investigated for possible use as pesticides (Blum, 1990).

Overview

Life Support

    A) This overview assumes that basic life support measures have been instituted.

Clinical Effects

    0.2.1) SUMMARY OF EXPOSURE
    A) USES: Ants are commonly encountered in houses and in the environment.
    B) TOXICOLOGY: Ants bites deliver a small amount of formic acid that causes local pain and irritation. Fire ant venom is delivered when the ants sting with a venom apparatus on the abdomen. The small inoculum and inefficient delivery mechanism means that significant clinical effects are uncommon from a single sting. The primary toxicities are acute hypersensitivity and anaphylactic reactions. Also, systemic effects may occur with multiple stings.
    C) EPIDEMIOLOGY: Ant bites/stings are common; severe clinical effects from stings are rare and are generally only seen after fire ant stings.
    D) WITH POISONING/EXPOSURE
    1) MILD TO MODERATE TOXICITY: Localized pain, urticaria, and erythema can occur from the bite of many ant species. Fire ant stings may cause more severe pruritus, generalized urticaria, formation of pustules or vesicles, and occasionally small areas of necrosis. Secondary infection of ant bites or stings is rare but has occurred.
    2) SEVERE TOXICITY: FIRE ANTS: Allergic reactions are more common with fire ant stings (approximately 16% of patients develop localized allergic reactions and approximately 0.6% develop anaphylaxis). The occurrence of anaphylaxis is not dependent upon the number of bites; anaphylaxis has occurred with fewer than 5 stings. Ulceration due to multiple stings has been reported. Seizures and neuropathies have been reported rarely after fire ant stings. Severe systemic toxicity, including hypotension, heart failure, acute lung injury, cerebral edema, liver failure, renal failure, and death have been reported following fire ant stings. These cases generally involve multiple stings (hundreds to thousands) and manifestations of severe anaphylaxis. OTHER ANTS: Bites from other ants can cause allergic reactions, but they are not as common or as severe.
    0.2.3) VITAL SIGNS
    A) WITH POISONING/EXPOSURE
    1) A mild fever may accompany fire ant sting. Dyspnea and hypertension may be seen with an allergic response.
    0.2.4) HEENT
    A) WITH POISONING/EXPOSURE
    1) Erythema and edema of the face, tongue, and lips as well as conjunctivitis may be seen after fire ant stings.
    0.2.6) RESPIRATORY
    A) WITH POISONING/EXPOSURE
    1) Dyspnea and asthma may occur in patients suffering from an allergic reaction to fire ants.
    0.2.7) NEUROLOGIC
    A) WITH POISONING/EXPOSURE
    1) Neuropathies may be seen following a fire ant sting, but are uncommon. Headache and syncope may occur. Seizures are rare but have been seen after fire ant stings.
    0.2.9) HEPATIC
    A) WITH POISONING/EXPOSURE
    1) Liver failure has been rarely reported.
    0.2.10) GENITOURINARY
    A) WITH POISONING/EXPOSURE
    1) Renal failure and nephrotic syndrome have been rarely reported.
    0.2.14) DERMATOLOGIC
    A) WITH POISONING/EXPOSURE
    1) Wheals leading to sterile vesicles and later to necrotic lesions may occur with fire ant stings. Pruritus and urticaria may also occur.
    0.2.19) IMMUNOLOGIC
    A) WITH POISONING/EXPOSURE
    1) Anaphylactoid-type reactions may be seen following fire ant stings.

Laboratory Monitoring

    A) No laboratory evaluation is indicated for most patients with ant envenomations.
    B) Monitor for evidence of anaphylaxis.
    C) Monitor serum electrolytes, renal function, hepatic enzymes, and urine output in patients with anaphylaxis or large numbers of stings.

Treatment Overview

    0.4.5) DERMAL EXPOSURE
    A) OVERVIEW
    1) Provide symptomatic care and local wound care.
    0.4.7) BITES/STINGS
    A) MANAGEMENT OF MILD TO MODERATE TOXICITY
    1) Antihistamines (diphenhydramine ADULT: 25 to 50 mg orally every 6 hours as needed; CHILD: 1 to 2 mg/kg orally every 6 hours as needed) should be provided for pruritus due to bites. Local wound care and tetanus prophylaxis should be given.
    B) MANAGEMENT OF SEVERE TOXICITY
    1) In patients with acute allergic reaction, oxygen therapy, bronchodilators, diphenhydramine, corticosteroids, vasopressors and epinephrine may be required. DERMAL EXPOSURE: As above, local wound care and symptomatic care.
    C) DECONTAMINATION
    1) PREHOSPITAL: Remove infested clothing, remove ants from the patient's skin, and wash skin.
    2) HOSPITAL: Remove clothes to ensure that there will not be ongoing envenomation. Remove ants from patient and wash skin.
    D) AIRWAY MANAGEMENT
    1) Airway compromise may develop secondary to severe anaphylaxis. Anaphylactic hypersensitivity reactions should be treated with epinephrine. Intubation and mechanical ventilation should be employed for airway protection in patients with anaphylaxis not rapidly improved with epinephrine.
    E) ANTIDOTE
    1) None
    F) PATIENT DISPOSITION
    1) HOME CRITERIA: The majority of patients can be treated at home with recommendations for antihistamines for pruritus, and local wound care instructions. Patients with generalized urticaria or pruritus, shortness of breath, or other symptoms suggestive of anaphylaxis should be instructed to call an ambulance and go to the hospital immediately.
    2) OBSERVATION CRITERIA: Patients that have anaphylactic symptoms should be observed for a minimum of 6 hours. Patients who require epinephrine require longer observation.
    3) ADMISSION CRITERIA: Patients with recurrence of anaphylactic symptoms following one dose of epinephrine should be admitted due to the high risk of recurrence.
    G) PITFALLS
    1) Failure to remove ants from the patient's skin and failure to remove the insects from clothing may lead to progressive symptoms.
    H) TOXICOKINETICS
    1) Ant venom is rapidly broken down and dermal effects will improve within 24 hours.
    I) DIFFERENTIAL DIAGNOSIS
    1) Hymenoptera stings may lead to similar hypersensitivity reactions. Contact dermatitis from environmental exposures may lead to similar clinical findings.

Range Of Toxicity

    A) TOXICITY: Hypersensitivity reactions are not dependent upon the number of stings. Anaphylaxis has been reported with less than 5 stings. The degree of dermal irritation, however, is increased with more stings. Fatalities have been reported, usually with large numbers of fire ant stings (hundreds to thousands); however, some patients with thousands of stings have had only local symptoms. Severe toxicity has only been well-described after fire ant stings.

Clinical Effects

Summary Of Exposure

    A) USES: Ants are commonly encountered in houses and in the environment.
    B) TOXICOLOGY: Ants bites deliver a small amount of formic acid that causes local pain and irritation. Fire ant venom is delivered when the ants sting with a venom apparatus on the abdomen. The small inoculum and inefficient delivery mechanism means that significant clinical effects are uncommon from a single sting. The primary toxicities are acute hypersensitivity and anaphylactic reactions. Also, systemic effects may occur with multiple stings.
    C) EPIDEMIOLOGY: Ant bites/stings are common; severe clinical effects from stings are rare and are generally only seen after fire ant stings.
    D) WITH POISONING/EXPOSURE
    1) MILD TO MODERATE TOXICITY: Localized pain, urticaria, and erythema can occur from the bite of many ant species. Fire ant stings may cause more severe pruritus, generalized urticaria, formation of pustules or vesicles, and occasionally small areas of necrosis. Secondary infection of ant bites or stings is rare but has occurred.
    2) SEVERE TOXICITY: FIRE ANTS: Allergic reactions are more common with fire ant stings (approximately 16% of patients develop localized allergic reactions and approximately 0.6% develop anaphylaxis). The occurrence of anaphylaxis is not dependent upon the number of bites; anaphylaxis has occurred with fewer than 5 stings. Ulceration due to multiple stings has been reported. Seizures and neuropathies have been reported rarely after fire ant stings. Severe systemic toxicity, including hypotension, heart failure, acute lung injury, cerebral edema, liver failure, renal failure, and death have been reported following fire ant stings. These cases generally involve multiple stings (hundreds to thousands) and manifestations of severe anaphylaxis. OTHER ANTS: Bites from other ants can cause allergic reactions, but they are not as common or as severe.

Vital Signs

    3.3.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) A mild fever may accompany fire ant sting. Dyspnea and hypertension may be seen with an allergic response.
    3.3.2) RESPIRATIONS
    A) WITH POISONING/EXPOSURE
    1) Dyspnea and wheezing may occur during hypersensitivity reactions, especially those in which an asthmatic patient has been bitten (Triplett, 1973; Lockey, 1974).
    3.3.3) TEMPERATURE
    A) WITH POISONING/EXPOSURE
    1) A mild fever for 24 to 48 hours may accompany fire ants' stings (Caro et al, 1957).
    3.3.4) BLOOD PRESSURE
    A) WITH POISONING/EXPOSURE
    1) HYPERTENSION may be seen in individuals experiencing the pain and/or allergic reaction symptoms to fire ant stings (Brown, 1972).
    3.3.5) PULSE
    A) WITH POISONING/EXPOSURE
    1) TACHYCARDIA may be seen in individuals experiencing the pain and/or allergic reaction symptoms to fire ant stings (Brown, 1972).

Heent

    3.4.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Erythema and edema of the face, tongue, and lips as well as conjunctivitis may be seen after fire ant stings.
    3.4.2) HEAD
    A) WITH POISONING/EXPOSURE
    1) Erythema and edema of the face, tongue and lips is one of the first signs of allergic reactions to fire ants stings (Brown, 1972; Caro et al, 1957).
    3.4.3) EYES
    A) WITH POISONING/EXPOSURE
    1) Systemic allergic reactions to fire ant stings may cause red, edematous conjunctivae (Brown, 1972).

Cardiovascular

    3.5.2) CLINICAL EFFECTS
    A) HEART FAILURE
    1) WITH POISONING/EXPOSURE
    a) Worsening heart failure has been reported in elderly patients (with underlying heart failure) after fire ant stings (deShazo et al, 2004).
    B) TACHYARRHYTHMIA
    1) WITH POISONING/EXPOSURE
    a) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): Tachycardia developed in a 64-year-old man who was stung on the hand by a Dinoponera gigantea black ant (Haddad et al, 2005).
    3.5.3) ANIMAL EFFECTS
    A) ANIMAL STUDIES
    1) LACK OF EFFECT
    a) FIRE ANT VENOM: Synthetic alkaloidal components known to be in the venom and suspended venom glands were tested in a mammalian cardiovascular survey preparation. Within the range of physiopharmacological considerations, no cardiovascular changes were noted (Buffkin & Russell, 1974).

Respiratory

    3.6.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Dyspnea and asthma may occur in patients suffering from an allergic reaction to fire ants.
    3.6.2) CLINICAL EFFECTS
    A) DYSPNEA
    1) WITH POISONING/EXPOSURE
    a) Dyspnea and bronchial asthma may occur in patients suffering from an allergic reaction to fire ants. This is especially true of individuals who have had asthma (Caro et al, 1957; Triplett, 1973).
    B) ACUTE LUNG INJURY
    1) WITH POISONING/EXPOSURE
    a) CASE REPORT: Pulmonary edema, following a lengthy hospital course which was complicated by sepsis and multiple organ failure, has been reported in one rare case involving a fire ant sting (Candiotti & Lamas, 1993).
    b) CASE REPORT: An 85-year-old female nursing home resident was found covered with fire ants. She was treated with antihistamines and corticosteroids but developed acute lung injury within 8 hours and died 3 days later (deShazo et al, 2004).

Neurologic

    3.7.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Neuropathies may be seen following a fire ant sting, but are uncommon. Headache and syncope may occur. Seizures are rare but have been seen after fire ant stings.
    3.7.2) CLINICAL EFFECTS
    A) NEUROPATHY
    1) WITH POISONING/EXPOSURE
    a) Several ant toxins have been shown to be neurotoxic in animals possibly due to the piperidine alkaloids in the venom, local compression due to edema, or direct nerve injury.
    1) Neuropathies have been reported in some cases of fire ant stings, but are rare (Fox et al, 1982). A right radial mononeuropathy has been reported (Lockey, 1990).
    B) HEADACHE
    1) WITH POISONING/EXPOSURE
    a) Syncope and headache have been seen after Samsum ant stings (Dib et al, 1992).
    C) SEIZURE
    1) WITH POISONING/EXPOSURE
    a) Seizures are rare, but have been seen after fire ant stings (Fox et al, 1982). Three grand mal seizures and a focal motor seizure were reported by one author (Lockey, 1990). Another report described 2 cases of grand mal seizures in adults stung by fire ants (Candiotti & Lamas, 1993).
    D) COMA
    1) WITH POISONING/EXPOSURE
    a) Coma was reported in one case of a sting by the Samsum ant (Dib et al, 1992).
    E) CEREBRAL EDEMA
    1) WITH POISONING/EXPOSURE
    a) CASE REPORT: Cerebral edema was reported in one adult following a sting by a fire ant (Candiotti & Lamas, 1993). The patient had a history of previous exposure to a fire ant sting and had manifestations of anaphylaxis.
    F) MALAISE
    1) WITH POISONING/EXPOSURE
    a) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): Malaise developed in a 64-year-old man who was stung on the hand by a Dinoponera gigantea black ant (Haddad et al, 2005).

Gastrointestinal

    3.8.2) CLINICAL EFFECTS
    A) NAUSEA AND VOMITING
    1) WITH POISONING/EXPOSURE
    a) Nausea may be seen during an allergic reaction to fire ants (Lofgren et al, 1975). Vomiting was reported in a few cases of stings by the Samsum ant (Dib et al, 1992).
    b) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): Nausea and vomiting developed in a 64-year-old man who was stung on the hand by a Dinoponera gigantea black ant (Haddad et al, 2005).
    B) HEMATOCHEZIA
    1) WITH POISONING/EXPOSURE
    a) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): A 64-year-old man with no history of digestive, hematological or vascular problems, experienced an episode of severe rectal bleeding approximately 3 hours after envenomation by a Dinoponera gigantea black ant in his left hand (Haddad et al, 2005).

Hepatic

    3.9.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Liver failure has been rarely reported.
    3.9.2) CLINICAL EFFECTS
    A) HEPATIC FAILURE
    1) WITH POISONING/EXPOSURE
    a) CASE REPORT: Liver failure was reported in one adult following a sting by a fire ant (Candiotti & Lamas, 1993). The patient had a history of prior exposure to a fire ant sting and had manifestations of anaphylaxis.

Genitourinary

    3.10.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Renal failure and nephrotic syndrome have been rarely reported.
    3.10.2) CLINICAL EFFECTS
    A) RENAL FAILURE SYNDROME
    1) WITH POISONING/EXPOSURE
    a) CASE REPORT: Renal failure secondary to acute tubular necrosis and multiple organ failure has been noted in an adult following a fire ant sting (Candiotti & Lamas, 1993). The patient had prior exposure to a fire ant sting and displayed evidence of anaphylaxis.
    B) TOXIC NEPHROPATHY
    1) WITH POISONING/EXPOSURE
    a) NEPHROTIC SYNDROME: A 3-year-old child developed minimal change nephrotic syndrome 2 weeks after envenomation by fire ants (Solenopsis invicta). The patient was treated with prednisolone and symptoms rapidly resolved (Swanson & Leveque, 1990).

Hematologic

    3.13.3) ANIMAL EFFECTS
    A) ANIMAL STUDIES
    1) BLOOD DISORDER
    a) Fire ant (Solenopsis invicta) venom has been shown to activate platelets and leukocytes in animal studies (Javors et al, 1993).
    b) Harvester ant (Pogonomyrmex barbatus) venom has anticoagulant activity in animal models (Tan & Ponnudurai, 1992).

Dermatologic

    3.14.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Wheals leading to sterile vesicles and later to necrotic lesions may occur with fire ant stings. Pruritus and urticaria may also occur.
    3.14.2) CLINICAL EFFECTS
    A) BULLOUS ERUPTION
    1) WITH POISONING/EXPOSURE
    a) Wheals leading to sterile vesicles and later to necrotic lesions are common reactions to the stings of the fire ant (Caro et al, 1957).
    b) "HALO WOUND": Stings from Pogonomyrex result in an immediate purplish hemorrhagic spot which is followed by a small blister with a halo of erythematous tissue (Smith, 1982; Cohen, 1992).
    c) CASE REPORT: A 40-year-old man presented to the emergency department with multiple ulcerated skin lesions on his abdomen, shoulders, arms, neck, and head after having been bitten by safari ants. At the time of presentation, the patient was also unresponsive (Glasgow Coma Score of 6), hypoglycemic with a blood glucose level of 13 mg/dL (reference range 70 to 100 mg/dL), and hypotensive. A diagnosis of anaphylaxis secondary to the ant bites was made. With supportive care and antibiotic administration for a suspected secondary infection, the patient recovered and was discharged 5 days later (Chianura & Pozzi, 2010).
    B) PUSTULE
    1) WITH POISONING/EXPOSURE
    a) Pustules may develop after fire ant stings (deShazo et al, 2004).
    C) ITCHING OF SKIN
    1) WITH POISONING/EXPOSURE
    a) Often severe pruritus may occur with fire ant stings (Caro et al, 1957) as well as other ant stings (Lewis & de la Lande, 1967).
    D) URTICARIA
    1) WITH POISONING/EXPOSURE
    a) Generalized urticaria may occur after fire ant stings (Caro et al, 1957).
    b) Wheal and erythema are common signs of ant envenomization of many different species (Lewis & de la Lande, 1967; Caro et al, 1957).
    E) LOCAL INFECTION OF WOUND
    1) WITH POISONING/EXPOSURE
    a) Secondary infections may occur at the site of the pustules. Several cases requiring systemic antibiotics have been reported (Parrino et al, 1981).
    1) Some cases have required surgical debridement and skin grafting.
    2) Nineteen cases required partial or total amputation of an extremity due to complications (Parrino et al, 1981).
    F) PAIN
    1) WITH POISONING/EXPOSURE
    a) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): A 64-year-old man developed severe pain and cold sweating following a sting by a Dinoponera gigantea black ant on his left hand. Despite the use of analgesics and immersion in hot water and ice, his symptoms did not improve. After 8 hours, his intense pain improved; however, the area of the sting remained moderately painful for about 24 hours. Two days after the envenomation, he presented with only mild local edema and erythema (Haddad et al, 2005).

Immunologic

    3.19.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Anaphylactoid-type reactions may be seen following fire ant stings.
    3.19.2) CLINICAL EFFECTS
    A) ANAPHYLACTOID REACTION
    1) WITH POISONING/EXPOSURE
    a) The venom of Solenopsis species has the ability to sensitize individuals after the first sting and then create a generalized allergic response on subsequent stings. In this way it is similar to Hymenoptera (bee, wasp) stings (Triplett, 1973).
    b) Anaphylactoid-type reactions have been seen with Solenopsis (Favorite, 1958; Brown, 1972; Candiotti & Lamas, 1993), Pachycondyla, and Pogonomyrex species (Pinnas et al, 1977; Dib et al, 1992). At least 4 different allergens have been isolated (Hoffman et al, 1988; Nordvall et al, 1988).
    c) FIRE ANTS (SOLENOPSIS SPECIES)
    1) Classic allergic reaction symptoms may be seen, and are not related to the number of stings. Fewer than 5 may cause a reaction in sensitive individuals (Candiotti & Lamas, 1993) while hundreds of stings have occurred without systemic symptoms (Brown, 1972; Rhoades et al, 1975).
    2) As many as 16% of people stung may exhibit allergic reactions (Reed & Butcher, 1990), and 0.6% of those envenomized develop anaphylactic-type reactions (Butcher & Reed, 1988).
    3) One study found 32 anaphylactic deaths from fire ant stings which occurred in Texas, Florida, Louisiana, and Georgia (Rhoades et al, 1989).
    4) CASE REPORT: A 30-year-old woman died from anaphylaxis after sustaining multiple fire ant stings. Postmortem anti-fire ant IgE levels were 5654 ng/mL (greater than 1 ng/mL is considered positive) (Prahlow & Barnard, 1998).
    5) CASE REPORT: A 72-year-old male nursing home resident was found covered with fire ants. He complained of feeling hot, rapidly developed tongue swelling and within minutes developed cardiopulmonary arrest. He was resuscitated and taken to the hospital but developed progressive respiratory failure and died within 24 hours. Serum tryptase one hour after hospital arrival was 23 ng/mL, confirming anaphylaxis (deShazo et al, 2004).
    6) CASE REPORT (INFANT): A 3-month-old infant died from anaphylaxis after receiving multiple stings from an indoor native fire ant, later identified to be Solenopsis xyloni. Post-mortem exam revealed approximately 40 erythematous lesions without pustules, congested parenchyma in the lungs, and mild laryngeal edema. Laboratory analysis showed a tryptase concentration of 23.9 ng/mL (normal 11.4 ng/mL). A radioallergosorbent test (RAST) demonstrated specific IgE antibody binding of 1.4% to Solenopsis richteri venom, but was negative for IgE antibody binding to Solenopsis invicta venom, suggesting primary sensitization to Sol 2 allergen from the imported fire ant species, S. richteri (More et al, 2008).
    7) CASE REPORTS: Anaphylactic reactions were reported in two patients who were stung multiple times by red imported fire ants (Levy et al, 2004).
    a) The first patient, a 33-year-old woman, experienced generalized pruritus and urticaria of her neck and trunk within 5 to 10 minutes after being stung several times on her neck by a single red imported fire ant (RIFA). Subsequently, she developed dyspnea, but recovered following treatment with diphenhydramine and epinephrine. Prior to this episode, the patient had been stung by RIFAs on several occasions, only developing large local reactions.
    b) The second patient, a 22-month-old child with a history of reactive airways disease and perennial allergic rhinitis, developed angioedema and laryngeal edema after having been stung multiple times by RIFAs. The patient recovered following treatment with epinephrine, nebulized albuterol, and corticosteroids. Prior to this episode, the child had been stung by RIFAs on 3 separate occasions without incident (Levy et al, 2004).
    d) HARVESTER ANTS (POGONOMYRMEX SPECIES)
    1) Allergic reactions have also occurred after exposure to harvester ant stings, but these reactions are rare.
    2) CASE REPORT: A 9-year-old who was stung on the hand developed moderately severe asthma and lethargy which lasted for 12 hours. The child had a history of asthma, but had no active illness at the time of the attack (Lockey, 1974).
    3) CASE REPORT: A 12-year-old boy with a history of hay fever developed urticarial rash, wheezing, and dyspnea following a bite from a red harvester ant (Formica rufa). Skin testing was positive to harvester ant extract, and serum IgE levels were elevated (Schmid-Grendelmeier et al, 1997).
    e) MYRMECIA PILOSULA (JACK JUMPER ANTS)
    1) CASE SERIES: Four cases of fatal anaphylaxis following jack jumper ant sting have been reported; all victims were men 40-year-old or over with significant comorbidities. In three patient sera, IgE specific for Myrmecia pilosula venom was detected. One death may have been caused by the inchman ant, Myrmecia forficata, rather than the jack jumper. It is suggested that cross-reactivity between different Myrmecia venoms may lead to anaphylaxis after the sting of a species not previously encountered (Brown et al, 2001).
    a) Although three victims had known ant-sting allergy, only one carried adrenaline for auto-injection, which he did not use. Two victims were taking angiotensin-converting enzyme inhibitors (combined with a beta blocker in one victim); these drugs may increase risk of severe anaphylaxis (Brown et al, 2001).
    b) Inhibitors of ACE (kininase) may worsen the severity of anaphylaxis in sensitized patients, possibly because of decreased breakdown of vasodilator kinins activated during anaphylaxis or compromise of compensatory activation of the renin-angiotensin system. Beta blockers can impair the endogenous adrenergic stress response and counteract and imbalance the effect of exogenous adrenaline (Brown et al, 2001).
    f) SAFARI ANTS
    1) CASE REPORT: A 40-year-old man presented to the emergency department with multiple ulcerated skin lesions on his abdomen, shoulders, arms, neck, and head after having been bitten by safari ants. At the time of presentation, the patient was also unresponsive (Glasgow Coma Score of 6), hypoglycemic with a blood glucose level of 13 mg/dL (reference range 70 to 100 mg/dL), and hypotensive. A diagnosis of anaphylaxis secondary to the ant bites was made. With supportive care and antibiotic administration for a suspected secondary infection, the patient recovered and was discharged 5 days later (Chianura & Pozzi, 2010).
    g) RHYTIDOPONERA METALLICA (GREEN HEAD ANTS)
    1) CASE REPORT: Anaphylaxis, manifested by generalized urticaria, facial angioedema, and persistent abdominal pain and lethargy, occurred in a 4-year-old girl approximately 20 minutes after reportedly being stung by 3 green head ants (Rhytidoponera metallica). Following supportive treatment with oral prednisone and promethazine, given at the local hospital, the patient recovered and was discharged home. Venom-specific IgE testing and immunotherapy to green head ant venom was not available (Mehr & Brown, 2012).
    B) LYMPHADENOPATHY
    1) WITH POISONING/EXPOSURE
    a) DINOPONERA GIGANTEA BLACK ANT (FALSE TOCANDIRA): Axillary lymphadenopathy developed in a 64-year-old man who was stung on the hand by a Dinoponera gigantea black ant (Haddad et al, 2005).
    C) HYPERSENSITIVITY REACTION MEDIATED BY ANTIBODY
    1) WITH POISONING/EXPOSURE
    a) A 2-part study examined the prevalence of allergic sensitization to imported fire ants (IFA) in children (n=183) living in an endemic region of the southeastern United States. In the first part, a cross-sectional, blinded survey of discarded serum samples from children (aged, 6 days to 20 years) revealed serum IgE anti-IFAV antibodies in 7.1% of 0- to 1-year-olds, 57.1% of 2- to 5-year-olds, 64.4% of 6- to 10-years-olds, and 65% of 11- to 20-year-olds. Serum IgG anti-IFAV antibodies were detected in 11.9% of 0- to 1-year-olds to 97.5% in 11- to 20-year-olds. In the second part of the study, a questionnaire which was used to collect information about insect stings and bites from 182 children found that 38.6% of the children had been stung by an IFA in the previous month; 23.9% of these children had more than 6 stings per month (Partridge et al, 2008).

Laboratory Monitoring

Monitoring Parameters Levels

    4.1.1) SUMMARY
    A) No laboratory evaluation is indicated for most patients with ant envenomations.
    B) Monitor for evidence of anaphylaxis.
    C) Monitor serum electrolytes, renal function, hepatic enzymes, and urine output in patients with anaphylaxis or large numbers of stings.
    4.1.2) SERUM/BLOOD
    A) No laboratory evaluation is indicated for most patients with ant envenomations.
    B) Monitor serum electrolytes, renal function, and hepatic enzymes in patients with anaphylaxis or large numbers of stings.
    4.1.3) URINE
    A) Monitor urine output in patients with anaphylaxis or large numbers of stings.
    4.1.4) OTHER
    A) OTHER
    1) MONITORING
    a) Monitor for evidence of anaphylaxis.
    2) OTHER
    a) Patients may be skin tested to determine the sensitivity to fire ants and other Hymenoptera. Such a test may aid in determining if desensitization is advisable (Brown, 1972) Triplett, 1973).

Methods

    A) MULTIPLE ANALYTICAL METHODS
    1) Although the venoms may be isolated by gas chromatography and mass spectrometry (Brand et al, 1972), this is generally not practical in the hospital laboratory.

Treatment

Life Support

    A) Support respiratory and cardiovascular function.

Patient Disposition

    6.3.6) DISPOSITION/BITE-STING EXPOSURE
    6.3.6.1) ADMISSION CRITERIA/BITE-STING
    A) Patients with recurrence of anaphylactic symptoms following one dose of epinephrine should be admitted due to the high risk of recurrence.
    6.3.6.2) HOME CRITERIA/BITE-STING
    A) The majority of patients can be treated at home with recommendations for antihistamines for pruritus, and local wound care instructions. Patients with generalized urticaria or pruritus, shortness of breath, or other symptoms suggestive of anaphylaxis should be instructed to call an ambulance and go to the hospital immediately.
    6.3.6.5) OBSERVATION CRITERIA/BITE-STING
    A) Patients that have anaphylactic symptoms should be observed for a minimum of 6 hours. Patients who require epinephrine require longer observation.

Monitoring

    A) No laboratory evaluation is indicated for most patients with ant envenomations.
    B) Monitor for evidence of anaphylaxis.
    C) Monitor serum electrolytes, renal function, hepatic enzymes, and urine output in patients with anaphylaxis or large numbers of stings.

Dermal Exposure

    6.9.1) DECONTAMINATION
    A) Remove clothes to ensure that there will not be ongoing envenomation. Remove ants from patient and wash skin.
    6.9.2) TREATMENT
    A) SUPPORT
    1) MANAGEMENT OF MILD TO MODERATE TOXICITY
    a) Antihistamines (eg, diphenhydramine) should be provided for pruritus due to bites. Local wound care and tetanus prophylaxis should be given. Local wound care and tetanus prophylaxis should be given.
    2) MANAGEMENT OF SEVERE TOXICITY
    a) In patients with acute allergic reaction, oxygen therapy, bronchodilators, diphenhydramine, corticosteroids, vasopressors and epinephrine may be required. DERMAL EXPOSURE: As above, local wound care and symptomatic care.
    B) LOCALIZED PAIN
    1) This has most often been treated by a combination of antihistamines, steroids, antibiotics, and analgesics.
    2) Laboratory and clinical experiments suggest these agents should be used on a symptomatic basis only, except for steroids which appear to lessen the reaction if given immediately post envenomation (Buffkin & Russell, 1974).
    3) An ointment mixture of neomycin sulfate, dexamethasone sodium phosphate, and lidocaine appeared to aid the most in reducing the discomfort from the local lesions if applied immediately post envenomation.
    4) Various treatment measures were tested on stung rabbits. The rabbits served as their own controls. One group of stings was treated with topical triamcinolone acetonide (0.1 percent) immediately after the stings and twice daily (Parrino et al, 1981).
    a) Another group of stings were treated when the pustules developed (24 hours post sting) by abrading the pustules daily for 7 days with a Betadine surgical scrub brush.
    b) No differences in clinical course, gross appearance, nor histology were noted between the control and treatment groups.
    5) A randomized controlled trial was conducted comparing the efficacy of Mitigator Bite and Sting treatment, a commercially available topical paste consisting of water, walnut shells, papain, and sodium bicarbonate, with calamine lotion for treatment of pain induced by fire ant stings. Twenty-four volunteers were exposed to fire ant stings on both forearms and then, 90 seconds to 10 minutes later, were treated with Mitigator paste on one arm and calamine lotion on the other arm. Pain was recorded using a visual analog scale 60 seconds, 20 minutes, and 3 days following exposure. The results of the study showed that there was no significant difference in the visual analog scale pain scores between the Mitigator paste group and the calamine lotion group at 60 seconds (23.9 mm vs 24.5 mm; p=0.861), at 20 minutes (7.6 mm vs 12.7 mm; p=0.147), and at 3 days (2.4 mm vs 2.9 mm; p=0.668) post-exposure (Hile et al, 2006).
    6) FORMIC ACID STINGS
    a) Some relief may be obtained by applying an alkaline solution such as baking soda or dilute household ammonia (Smith, 1982).

Abstracts

Case Reports

    A) INFANT
    1) A healthy 16-month-old child fell into a fire ant hill. She had stings over her entire body. The ants were immediately removed and the child bathed. The child experienced respiratory difficulties while this was being done. Mouth-to-mouth resuscitation was given by the mother (an RN) and the child was transported to the local emergency department by emergency medical services. CPR was performed in transit and on arrival.
    a) She survived on support for 6 more days and expired when she showed signs of ischemic brain death (Rhoades et al, 1989).
    2) A 5-day-old infant was found in his crib "covered with ants". Upon arrival at the hospital he was apneic and asystolic, in shock, with metabolic acidosis, coagulopathy, and no evidence of cerebral function. It is estimated he received 2000 stings on the face and arms.
    a) He was treated with supportive care, ventilation, pressors, diphenhydramine, antibiotics, bicarbonate, and methylprednisolone. Spontaneous respirations were again seen 16 hours postadmission. The patient was discharged 40 days postexposure (Hardwick et al, 1992).
    B) ADULT
    1) Not all fire ant stings will result in systemic symptoms. An 84-year-old woman with senile dementia was found in bed with thousands of ants crawling on her (Diaz et al, 1989). She received about 10,000 stings and was admitted to the hospital where she was given fluid hydration, antihistamines, and antibiotics. She did not demonstrate any systemic or immunologic reactions. The ants were identified as Solenopsis invicta.
    2) A 49-year-old man who had been drinking heavily fell asleep on a fire ant hill. A few hours later he had thousands of ants crawling on him. Later he was taken to the hospital with approximately 5,000 lesions (1 to 3 mm in diameter) on his face, trunk, and extremities.
    a) Vital signs were normal. By the next day, no systemic symptoms were noted (other than a hangover), but the lesions were more swollen and erythematous. Lab tests were normal, the pustules contents did not contain microorganisms. The patient was given zinc oxide and 1% hydrocortisone twice daily, topically for 12 days. When discharged, all lesions had healed, leaving small white scars (Smith & Smith, 1971).
    3) A 16 year old adolescent fell on a fire ant hill and sustained several hundred stings on his shoulder and neck. The affected areas were washed and the patient sought medical care for treatment of local skin effects. The patient had no obvious systemic reactions. He was discharged after being given a dose of diphenhydramine.
    a) Approximately 12 hours following the stings, the individual became confused, collapsed and seized. The patient arrived at the emergency room in a postictal state. Physical findings were not significant. The patient was discharged after 2 days (Candiotti & Lamas, 1993).
    4) A 32 year old woman sustained an ant bite to the foot. She had a prior history of developing a rash after being stung by a fire ant. No immediate reactions were noted. A short time later she collapsed. At the time of admission to a local hospital she was hypotensive and had a generalized urticarial rash.
    a) The evening following the ant sting, the patient had a grand mal seizure and was intubated. A CT scan showed diffuse cerebral edema. Renal failure secondary to acute tubular necrosis and multiple organ failure developed.
    b) The patient had a lengthy and complicated course in the intensive care unit, with sepsis, pulmonary edema, hemorrhagic diathesis, renal and liver failure. The patient died after 82 days of hospitalization (Candiotti & Lamas, 1993).

Range Of Toxicity

Summary

    A) TOXICITY: Hypersensitivity reactions are not dependent upon the number of stings. Anaphylaxis has been reported with less than 5 stings. The degree of dermal irritation, however, is increased with more stings. Fatalities have been reported, usually with large numbers of fire ant stings (hundreds to thousands); however, some patients with thousands of stings have had only local symptoms. Severe toxicity has only been well-described after fire ant stings.

Minimum Lethal Exposure

    A) GENERAL/SUMMARY
    1) AUSTRALIAN BULLDOG ANT: As few as 30 stings have been said to be fatal (Burton, 1977), but this statement is not well documented.
    2) ALLERGIC REACTIONS: To the stings of various ant species are not related to the number of stings. Serious reactions may occur with fewer than 5 stings (Brown, 1972).

Maximum Tolerated Exposure

    A) GENERAL/SUMMARY
    1) The maximum number of stings to cause systemic reactions is unknown. Hundreds of stings have occurred without systemic symptoms (Rhoades et al, 1975).

Toxicity Information

    7.7.1) TOXICITY VALUES
    A) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 0.25-0.62 mg/kg for 24H
    B) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 50-60 mg/kg for 24H
    C) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 10 mg/kg for 24H
    D) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 1.7-6.5 mg/kg for 24H
    E) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 6 mg/kg for 24H
    F) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 38 mg/kg for 24H
    G) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 2-5 mg/kg for 24H
    H) References: Schmidt et al, 1980 Lewis & de la Lande, 1967
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 10 mg/kg for 24H

Pharmacology Toxicology

Toxicologic Mechanism

    A) BY ANT -
    1) AUSTRALIAN BULLDOG ANT (Myrimica species) - have a proteinaceous venom containing at least 8 constituents. It has histamine 2%, as well as kinins, hyaluronidase, and a powerful phospholipase-A. It is similar to wasp venom (James Jr, 1976).
    a) It does not posses bradykinin-releasing activity but does have a non-histamine smooth muscle relaxant. It also has hemolytic activities (Clarke, 1986).
    b) The venom also contains histamine, releases cyclooxygenase, and a heat sensitive hemolytic factor (Matszek, 1994).
    2) FIELD ANTS (Formica species) - Spray formic acid into a wound created by their mandibles (Smith, 1982). Members of the Formicinae and Myrmicinae genera possess formic acid.
    3) FIRE ANTS -
    a) The fire ant has a necrotizing toxin similar to that of the brown recluse spider. The toxin (solenamine) is also antimycotic, antibacterial and insecticidal (Brown, 1972; Blum et al, 1958; Adrouny et al, 1956).
    b) The major components, loosely called solenamine are 2-methyl-6-n-alkyl (or alkenyl) piperidines (Adrouny, 1966) which are water soluble and do not cause allergic reactions (Stafford et al, 1989).
    c) The venom contains little protein (0.1% of venom weight) but also contains phospholipase and hyaluronidase. Some of the proteins identified have been allergenically active (Baer et al, 1979; Brand et al, 1972).
    d) These alkaloids were found in the 2 varieties of imported fire ants as well as S. xyloni and S. geminata, which are native to the United States. Four protein allergens have been isolated.
    e) Soli I has a molecular weight of 37,000, has 2 peptide chains and is about 2 to 5% of the various venom protein. Soli II is a single chain of peptides with a weight of 28,000. It is about 67% of venom protein.
    f) Soli III is about 20% of the protein, is a single chain weighing 26,000. Soli IV is about 9%, weight 15,000 and is a single chain. All are basic proteins (Stafford et al, 1989).
    g) The fire ant venom induces paralysis in insects (Blum et al, 1958). When solenamine was injected (2mg) in rabbit skin, a reaction similar to that of a fire ant stings was recorded (Jung et al, 1963).
    h) RAST analysis showed that although the venom of S. invicta was different from those found in S. geminata, S. richteri, and S. xyloni, it is thought to have considerable cross-reactivity (Baer et al, 1979).
    4) HARVESTER ANTS (Pogonomyrex species) - Their venom is a complex mixture of enzymes including hemolysins, phopholipases, and neurotoxins (Smith, 1982; Schmidt & Blum, 1978).
    a) The agent responsible for the direct lysis of erythrocytes by P. barbatus is a basic polypeptide with a molecular weight of approximately 3500. It closer resembles melittin, the hemolytic property found in honey bee venom.
    b) There is also a polypeptide of approximate weight 8000 which is not hemolytic, but unlike barbatolysin, is lethal to mice (Bernheimer et al, 1980).
    5) JUMPER ANTS - The venom is thought to contain histamine, hemolytic and eicosanoid-releasing factors (Matuszek et al, 1992).
    6) MONOMORIUM SPECIES - Various 2,5-dialkylpyrrolidines are known to be present in the alkaloidal venom these Afro-tropical group of ants (Jones et al, 1989).
    7) ECATOMMA SPECIES - The toxic component of the Amazonian selva ant (Ecatomma tuberculatum) has a protein that appears to form ion pores in cell membranes (Arseniev, 1994).
    B) BY CHEMICAL -
    1) IRIDOMYRMECIN - A penoid lactone has been isolated from ants in the subfamily Dolichoderinae. It has antibiotic properties and induces tremors in insects (Blum et al, 1958). It is found in Argentine ants (Cavill & Robertson, 1965).
    2) TERPENOIDS - Such as 2-methyhept-2-en-6-one have been isolated from ants in the Dolichoderinae genera. Citral has been seen in Atta sexdens rubropilosa and both citral and citronellal in Acanthomyops claviger (an ant in the Formicinae).
    a) Limonene has been isolated from Myrmicaria natalensis (Cavill & Robertson, 1965). Many of these terpenoids are considered attractants and repellants in the ants themselves and their role in human intoxication is minimal.

References

General Bibliography

    1) AMA Department of DrugsAMA Department of Drugs: AMA Evaluations Subscription, American Medical Association, Chicago, IL, 1992.
    2) Adrouny GA, Derbes VJ, & Jung RC: Isolation of a hemolytic component of fire ant venom. Science 1956; 130:449.
    3) Adrouny GA: The fire ants fire. Bull Tulane Univ Med Faculty 1966; 25:76-72.
    4) Am Acad Neurol: Practice parameter: The management of concussion in sports (summary statement). Report of the Quality Standards Subcommittee. Neurology 1997; 48:581-585.
    5) Anon: Fire ants sting. JAMA 1960; 172:1221-1222.
    6) Anon: Wild spread of fire ants. Lancet 1990; 336:499.
    7) Baer H, Liu TY, & Anderson MC: Protein components of fire ant venom (Solenopsis invicta). Toxicon 1979; 17:397-405.
    8) Battison C, Andrews PJ, Graham C, et al: Randomized, controlled trial on the effect of a 20% mannitol solution and a 7.5% saline/6% dextran solution on increased intracranial pressure after brain injury. Crit Care Med 2005; 33(1):196-202.
    9) Bernheimer AW, Avigad LS, & Schmidt JO: A hemolytic polypeptide from the venom of the red harvester ant, Pogonomyrmex barbatus. Toxicon 1980; 18:271-278.
    10) Blum MS, Walker JR, & Callahan PS: Chemical, insecticidal, and antibiotic properties of fire ant venom. Science 1958; 128:306-307.
    11) Blum MS: Venomous alkaloids of myrmicine ants (abstract). J Toxicol Toxin Rev 1990; 9:58.
    12) Brand JM, Blum MS, & Fales HM: Fire ant venoms; comparative analyses of alkaloidal components. Toxicon 1972; 10:259-271.
    13) Brophy GM, Bell R, Claassen J, et al: Guidelines for the evaluation and management of status epilepticus. Neurocrit Care 2012; 17(1):3-23.
    14) Brown LL: Fire ant allergy. South Med J 1972; 65:273-277.
    15) Brown SGA, Wiese M, Blackman KE, et al: Ant venom immunotherapy: a double-blind, placebo-controlled, crossover trial. Lancet 2003; 361:1001-6.
    16) Brown SGA, Wu QX, & Kelsall GRH: Fatal anaphylaxis following jack jumper ant sting in southern Tasmania. MJA 2001; 175:644-647.
    17) Buffkin DC & Russell FE: A study of the venom of the imported fire ant: physiopharmacology, chemistry and therapeutics. Proc West Pharmacol Soc 1974; 17:223-226.
    18) Bullock R, Chesnut RM, & Clifton G: Guidelines for the management of severe head injury. Eur J Emerg Med 1996; 2:109-127.
    19) Burroughs MAJR & Elston DM: What's eating you? Fire ants. Cutis 2005; 75:85-89.
    20) Burton R: Venomous Animals, Crescent Books, London, England, 1977.
    21) Butcher BT & Reed MA: Crossed immunoelectrophoretic studies of whole body extracts and venom from the imported fire ant Solenopsis invicta. J Allergy Clin Immunol 1988; 81:33-40.
    22) Candiotti KA & Lamas AM: Adverse neurologic reactions to the sting of the imported fire ant. Int Arch Allergy Immunol 1993; 102:417-420.
    23) Caro MR, Derbes VJ, & Jung R: Skin responses to the sting of the imported fire ant. (Solenopsis saevissima). Arch Dermatol 1957; 75:475-488.
    24) Cavill GWK & Robertson PL: Ant venoms, attractants, and repellants. Science 1965; 149:1337-1345.
    25) Chamberlain JM, Altieri MA, & Futterman C: A prospective, randomized study comparing intramuscular midazolam with intravenous diazepam for the treatment of seizures in children. Ped Emerg Care 1997; 13:92-94.
    26) Chianura L & Pozzi F: A 40-year-old man with ulcerated skin lesions caused by bites of safari ants. Am J Trop Med Hyg 2010; 83(1):9-9.
    27) Chin RF , Neville BG , Peckham C , et al: Treatment of community-onset, childhood convulsive status epilepticus: a prospective, population-based study. Lancet Neurol 2008; 7(8):696-703.
    28) Choonara IA & Rane A: Therapeutic drug monitoring of anticonvulsants state of the art. Clin Pharmacokinet 1990; 18:318-328.
    29) Clarke PS: The natural history of sensitivity to jack jumper ants (Hymenoptera formicidae Myrmecia pilosula) in Tasmania. Med J Aust 1986; 145:564-566.
    30) Cohen PR: Imported fire ant stings: clinical manifestations and treatment. Pediatr Dermatol 1992; 9:44-48.
    31) Diaz JD, Lockey RF, & Stablein MD: Multiple stings by imported fire ants (Solenopsis invicta), without systemic effects. South Med J 1989; 82:775-777.
    32) Dib G, Ferguson RK, & Sljivic V: Hypersensitivity to Samsum ant (letter). Lancet 1992; 339:552-553.
    33) Duplantier JE, Freeman TM, & Bahna SL: Successful rush immunotherapy for anaphylaxis to imported fire ants. J Aller Clin Immunol 1998; 855-856.
    34) Favorite FG: The imported fire ant. Public Health Rep 1958; 73:446-448.
    35) Feldman Z, Kanter MJ, & Robertson CS: Effect of head elevation on intracranial pressure, cerebral perfusion pressure, and cerebral blood flow in head-injured patients. J Neurosurg 1992; 76:207-211.
    36) Ford SA, Baldo BA, & Weiner J: Identification of jack-jumper ant (Myrmecia pilosula) venom allergens. Clin Exp Allergy 1991; 21:167-171.
    37) Fox RW, Lockey RF, & Bukantz SC: Neurological sequelae following the imported fire ant sting. J Allerg Clin Immunol 1982; 70:120.
    38) Haddad JV, Cardoso JL, & Moraes RH: Description of an injury in a human caused by a false tocandira (Dinoponera gigantea, Perty, 1833) with a revision on folkloric, pharmacological and clinical aspects of the giant ants of the genera Paraponera and Dinoponera (sub-family Ponerinae). Rev Inst Med Trop Sao Paulo 2005; 47(4):235-238.
    39) Hardwick W, Royall J, & Petitt B: Near fatal fire ant envenomation of a newborn. Pediatrics 1992; 90:622-624.
    40) Hegenbarth MA & American Academy of Pediatrics Committee on Drugs: Preparing for pediatric emergencies: drugs to consider. Pediatrics 2008; 121(2):433-443.
    41) Hile DC, Coon TP, Skinner CG, et al: Treatment of imported fire ant stings with mitigator sting and bite treatment--a randomized control study. Wilderness Environ Med 2006; 17(1):21-25.
    42) Hoffman DR, Dove DE, & Jacobson RS: Allergens in hymenoptera venom. XX Isolation of four allergens from imported fire ant (Solenopsis invicta) venom. J Allergy Clin Immunol 1988; 82:818-827.
    43) Hvidberg EF & Dam M: Clinical pharmacokinetics of anticonvulsants. Clin Pharmacokinet 1976; 1:161.
    44) Javors MA, Zhou W, & Maas JW: Effects of fire ant venom alkaloids on platelet and neutrophil function. Life Sci 1993; 53:1105-1112.
    45) Jones TH, Blum MS, & Escoubas P: Novel pyrrolidines in the venom of the ant Monomorium indicum. J Nat Prod 1989; 52:779-784.
    46) Jung RC, Derbes VJ, & Burch AD: Skin responses to solenamine, a hemolytic component of fire ant venom. Derm Trop 1963; 2:241-244.
    47) Kirkpatrick PJ: On guidelines for the management of the severe head injury (editorial). J Neurol Neurosurg Psychiatr 1997; 62:109-111.
    48) Levy AL , Wagner JM , & Schuman SH : Fire ant anaphylaxis: two critical cases in South Carolina. J Agromedicine 2004; 9(2):309-314.
    49) Lewis JC & de la Lande IS: Pharmacological and enzymatic constituents of the venom of an Australian "bulldog" ant Myrmecia myriformis. Toxicon 1967; 4:225-234.
    50) Lieberman P, Nicklas R, Randolph C, et al: Anaphylaxis-a practice parameter update 2015. Ann Allergy Asthma Immunol 2015; 115(5):341-384.
    51) Lieberman P, Nicklas RA, Oppenheimer J, et al: The diagnosis and management of anaphylaxis practice parameter: 2010 update. J Allergy Clin Immunol 2010; 126(3):477-480.
    52) Lockey RF: Systemic reactions to stinging ants. J Allergy Clin Immunol 1974; 54:132-146.
    53) Lockey RF: The imported fire ant: immunopathologic significance. Hosp Pract 1990; 109-124.
    54) Loddenkemper T & Goodkin HP: Treatment of Pediatric Status Epilepticus. Curr Treat Options Neurol 2011; Epub:Epub.
    55) Lofgren CS, Banks WA, & Glancey BM: Biology in control of imported fire ants. Ann Rev Entomol 1975; 20:1-30.
    56) Mackersie RC & Karagianes TG: Use of end-tidal carbon dioxide tension for monitoring induced hypocapnia in head-injured patients. Crit Care Med 1990; 18:764-765.
    57) Manno EM: New management strategies in the treatment of status epilepticus. Mayo Clin Proc 2003; 78(4):508-518.
    58) Matuszek MA, Hodgson WC, & Sutherland SK: Pharmacological studies of jumper ant (Myrmecia pilosula) venom: evidence for the presence of histamine, and haemolytic and eicosanoid-releasing factors. Toxicon 1992; 30:1081-1091.
    59) Mehr S & Brown S: A case of ant anaphylaxis. J Paediatr Child Health 2012; 48(3):E101-E104.
    60) Meixensberger J, Baunach S, & Amschler J: Influence of body position on tissue-pO2, cerebral perfusion pressure and intracranial pressure in patients with acute brain injury. Neurol Res 1997; 19:249-253.
    61) More DR , Kohlmeier RE , & Hoffman DR : Fatal anaphylaxis to indoor native fire ant stings in an infant. Am J Forensic Med Pathol 2008; 29(1):62-63.
    62) Muizelaar JP, Marmarou A, Ward JD, et al: Adverse effects of prolonged hyperventilation in patients with severe head injury: a randomized clinical trial.. J Neurosurg 1991; 75:731-739.
    63) National Heart,Lung,and Blood Institute: Expert panel report 3: guidelines for the diagnosis and management of asthma. National Heart,Lung,and Blood Institute. Bethesda, MD. 2007. Available from URL: http://www.nhlbi.nih.gov/guidelines/asthma/asthgdln.pdf.
    64) None Listed: The Brain Trauma Foundation. The American Association of Neurological Surgeons. The Joint Section on Neurotrauma and Critical Care. Hyperventilation. J Neurotrauma 2000a; 17(6-7):513-520.
    65) None Listed: The Brain Trauma Foundation. The American Association of Neurological Surgeons. The Joint Section on Neurotrauma and Critical Care. Use of mannitol. J Neurotrauma 2000; 17(6-7):521-525.
    66) Nordvall SL, Johansson SGO, & Ledford DK: Allergens of the imported fire ant. J Allergy Clin Immunol 1988; 82:567-576.
    67) Nowak RM & Macias CG : Anaphylaxis on the other front line: perspectives from the emergency department. Am J Med 2014; 127(1 Suppl):S34-S44.
    68) Parrino J, Kandawalla NM, & Lockey RF: Treatment of local skin response to improted fire ants. South Med J 1981; 74:1361-1364.
    69) Partridge ME, Blackwood W, Hamilton RG, et al: Prevalence of allergic sensitization to imported fire ants in children living in an endemic region of the southeastern United States. Ann Allergy Asthma Immunol 2008; 100(1):54-58.
    70) Paull BR & Coghlan TH: Fire ant allergy: whole body extract treatment failures. J Allergy Clin Immunol 1986; 77:141.
    71) Paull BR: Imported fire ant allergy: perspectives on diagnosis and treatment. Postgrad Med 1984; 76:155-162.
    72) Pinnas JL, Strunk RC, & Wang TM: Harvester ants sensitivity: In vitro and in vivo studies using whole body extraction venom. J Allerg Clin Immunol 1977; 59:10-16.
    73) Polin RS, Shaffrey ME, & Bogaev CA: Decompressive bifrontal craniectomy in the treatment of severe refractory posttraumatic cerebral edema. Neurosurgery 1997; 41:84-92.
    74) Prahlow JA & Barnard JJ: Fatal anaphylaxis due to fire ant stings. Am J Foren Med Pathol 1998; 19:137-142.
    75) Product Information: CEREBYX(R) intravenous injection, fosphenytoin sodium intravenous injection. Pfizer Labs (per FDA), New York, NY, 2014.
    76) Product Information: Dilantin(R) intravenous injection, intramuscular injection, phenytoin sodium intravenous injection, intramuscular injection. Parke-Davis (per FDA), New York, NY, 2013.
    77) Product Information: diazepam IM, IV injection, diazepam IM, IV injection. Hospira, Inc (per Manufacturer), Lake Forest, IL, 2008.
    78) Product Information: diphenhydramine HCl intravenous injection solution, intramuscular injection solution, diphenhydramine HCl intravenous injection solution, intramuscular injection solution. Hospira, Inc. (per DailyMed), Lake Forest, IL, 2013.
    79) Product Information: lorazepam IM, IV injection, lorazepam IM, IV injection. Akorn, Inc, Lake Forest, IL, 2008.
    80) Reed MA & Butcher BT: Imported fire ant (IFA) sensitivity: IFA-specific levels of serum IgG and IgG4. J Allergy Clin Immunol 1990; 85:737-742.
    81) Rhoades RB, Schafer WL, & Schmidt WH: Hypersensitivity to the imported fire ant. A report of 49 cases. J Allergy Clin Immunol 1975; 56:84-93.
    82) Rhoades RB, Stafford CT, & James FK Jr: Survey of fatal anaphylactic reactions to imported fire ant stings. J Allergy Clin Immunol 1989; 84:159-162.
    83) Rhoades RB: Fire ant allergy diagnosis and treatment. Immunol Allergy Pract 1987; 9:23-31.
    84) Sahuquillo J & Arikan F: Decompressive craniectomy for the treatment of refractory high intracranial pressure in traumatic brain injury. Cochrane Database Syst Rev 2006; 2006(1):CD003983-.
    85) Sakai K, Iwahashi K, & Terada K: Outcome after external decompression for massive cerebral infarction. Neurol Med Chir 1998; 38:131-136.
    86) Schmid-Grendelmeier P, Lundberg M, & Wuthrich B: Anaphylaxis due to a red harvest ant bite. Allergy 1997; 52:230-231.
    87) Schmidt JO & Blum MS: Pharmacological and toxicological properties of harvester ant, Pogonomyrmex badius, venom. Toxicon 1978; 16:645-651.
    88) Schmidt JO, Blum MS, & Overal WL: Comparatively lethality of venoms from stinging hymenoptera. Toxicon 1980; 18:469-474.
    89) Schneider GH, von Helden GH, & Franke R: Influence of body position on jugular venous oxygen saturation, intracranial pressure and cerebral perfusion pressure. Acta Neurochir 1993; 59(suppl):107-112.
    90) Schwartz MP: Fire ants: the march of death. J Fam Pract 1991; 33:406-410.
    91) Scott R, Besag FMC, & Neville BGR: Buccal midazolam and rectal diazepam for treatment of prolonged seizures in childhood and adolescence: a randomized trial. Lancet 1999; 353:623-626.
    92) Smith JD & Smith EB: Multiple fire ant stings. Arch Dermatol 1971; 103:438.
    93) Smith RL: Venomous Animals of Arizona. Bulletin 8245, Cooperative Extension Service, College of Agriculture, The University of Arizona, Tucson, Arizona, 1982.
    94) Sreenath TG, Gupta P, Sharma KK, et al: Lorazepam versus diazepam-phenytoin combination in the treatment of convulsive status epilepticus in children: A randomized controlled trial. Eur J Paediatr Neurol 2010; 14(2):162-168.
    95) Stablein JJ & Lockey RF: Adverse reactions to ant stings. Clin Rev Allergy 1987; 5:161-175.
    96) Stafford CT, Hoffman DR, & Rhoades RB: Allergy to imported fire ants. So Med J 1989; 82:1520-1527.
    97) Stafford CT, Hutto LS, & Rhoades RB: Imported fire ant as a health hazard. So Med J 1989a; 82:1515-1519.
    98) Stafford CT, Wise SL, & Robinson DA: Safety and efficacy of fire ant venom in the diagnosis of fire ant allergy. J Allergy Clin Immunol 1992; 90:653-661.
    99) Swanson GP & Leveque JA: Nephrotic syndrome associated with ant bite. Texas Medicine 1990; 86:39-41.
    100) Tan NH & Ponnudurai G: Comparative study of the enzymatic, hemorrhagic, procoagulant and anticoagulant activities of some animal venoms. Comp Biochem Physiol 1992; 103:299-302.
    101) Taylor A, Butt W, & Rosenfeld J: A randomized trial of very early decompressive craniectomy in children with traumatic brain injury and sustained intracranial hypertension. Childs Nerv Syst 2001; 17:154-162.
    102) Triplett RF: Sensitivity to the imported fire ant: successful treatment with immunotherapy. South Med J 1973; 66:477-480.
    103) Vanden Hoek,TL; Morrison LJ; Shuster M; et al: Part 12: Cardiac Arrest in Special Situations 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. American Heart Association. Dallas, TX. 2010. Available from URL: http://circ.ahajournals.org/cgi/reprint/122/18_suppl_3/S829. As accessed 2010-10-21.
    104) Wallace KL: Toxin-Induced Seizures. In: Brent J, Wallace KL, Burkhart KK, et al, eds. Critical Care Toxicology, Elsevier Mosby, Philadelphia, PA, 2005.
    105) deShazo RD, Griffing C, & Kwan TH: Dermal hypersensitivity reactions to imported fire ants. J Allergy Clin Immunol 1984; 74:841-847.
    106) deShazo RD, Kemp SF, deShazo MD, et al: Fire ant attacks on patients in nursing homes: an increasing problem. Am J Med 2004; 116:843-6.