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BETAHISTINE

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Classification   |    Detailed evidence-based information

Substances Included Synonyms

Therapeutic Toxic Class

    A) Betahistine is an orally active histamine analog. It acts as an agonist at H1 receptors.

Specific Substances

    1) Betahistine
    2) betahistine dihydrochloride
    3) PT-9
    4) N-methyl-2-(2-pyridyl)ethylamine dihydrochloride
    5) CAS 5638-76-6 (betahistine)
    6) CAS 5579-84-0 (betahistine hydrochloride)
    7) CAS 54856-23-4 (betahistine mesylate)
    8) Molecular Formula: C8-H12-N2.2HCl

Available Forms Sources

    A) FORMS
    1) Betahistine is no longer available in the United States. Betahistine is available in other countries as tablets containing 4 and 8 milligrams of betahistine.
    B) USES
    1) Oral betahistine has been evaluated in the treatment of vertigo and Meniere's disease in several controlled studies: however, conclusive evidence of significant efficacy is lacking. Betahistine is claimed to improve the microcirculation of the labyrinth resulting in reduced endolymphatic pressure (JEF Reynolds , 2000).

Overview

Life Support

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

Clinical Effects

    0.2.1) SUMMARY OF EXPOSURE
    A) WITH THERAPEUTIC USE
    1) No information is available on overdose in humans. The most common adverse effects associated with therapeutic administration of betahistine are nausea, vomiting, diarrhea, abdominal pain, headache, and sedation. Less common adverse effects include: fatigue, dizziness or faintness, insomnia, skin rash, flushing and increased micturition. Although rare, bronchoconstriction has been reported following oral administration of betahistine.

Treatment Overview

    0.4.2) ORAL/PARENTERAL EXPOSURE
    A) ACTIVATED CHARCOAL: Administer charcoal as a slurry (240 mL water/30 g charcoal). Usual dose: 25 to 100 g in adults/adolescents, 25 to 50 g in children (1 to 12 years), and 1 g/kg in infants less than 1 year old.
    B) GASTRIC LAVAGE: Consider after ingestion of a potentially life-threatening amount of poison if it can be performed soon after ingestion (generally within 1 hour). Protect airway by placement in the head down left lateral decubitus position or by endotracheal intubation. Control any seizures first.
    1) CONTRAINDICATIONS: Loss of airway protective reflexes or decreased level of consciousness in unintubated patients; following ingestion of corrosives; hydrocarbons (high aspiration potential); patients at risk of hemorrhage or gastrointestinal perforation; and trivial or non-toxic ingestion.
    C) ALLERGIC REACTION: MILD/MODERATE: Antihistamines with or without inhaled beta agonists, corticosteroids or epinephrine. SEVERE: Oxygen, aggressive airway management, antihistamines, epinephrine, corticosteroids, ECG monitoring, and IV fluids.
    D) Monitor blood pressure and respirations frequently.

Range Of Toxicity

    A) Doses up to 216 milligrams/day have been well tolerated by adults.

Clinical Effects

Summary Of Exposure

    A) WITH THERAPEUTIC USE
    1) No information is available on overdose in humans. The most common adverse effects associated with therapeutic administration of betahistine are nausea, vomiting, diarrhea, abdominal pain, headache, and sedation. Less common adverse effects include: fatigue, dizziness or faintness, insomnia, skin rash, flushing and increased micturition. Although rare, bronchoconstriction has been reported following oral administration of betahistine.

Vital Signs

    3.3.2) RESPIRATIONS
    A) WITH THERAPEUTIC USE
    1) BRONCHOCONSTRICTION - Asthmatic signs/symptoms may occur with therapy.

Heent

    3.4.3) EYES
    A) WITH THERAPEUTIC USE
    1) BLURRED VISION in association with faintness has been reported rarely during betahistine therapy (Seipel & Floam, 1975).

Cardiovascular

    3.5.2) CLINICAL EFFECTS
    A) ORTHOSTATIC HYPOTENSION
    1) WITH THERAPEUTIC USE
    a) Therapeutic oral doses of betahistine have not produced significant effects on blood pressure (Canty et al, 1981; Cook & James, 1981) Elbaz, 1988; (Seipel & Floam, 1975).
    1) Faintness has been reported occasionally with betahistine therapy, although it is unclear if this is related to blood pressure reduction (Cook & James, 1981).

Respiratory

    3.6.2) CLINICAL EFFECTS
    A) BRONCHOSPASM
    1) WITH THERAPEUTIC USE
    a) Dose-dependent bronchoconstriction has been reported following administration of aerosolized betahistine to both non-asthmatic and asthmatic patients. Inhaled histamine has induced greater bronchoconstriction than inhaled betahistine (White et al, 1987).
    b) CASE REPORT - A 28-year-old female with atopy and reactive airways developed betahistine-induced bronchospasm after taking as little as 1.20 milligrams of betahistine orally (Jimenez et al, 1996).
    c) Bronchospasm can occur in asthmatic patients treated with intravenous histamine but has not been studied with betahistine (Schmidt & Huizing, 1992).

Neurologic

    3.7.2) CLINICAL EFFECTS
    A) CENTRAL NERVOUS SYSTEM DEFICIT
    1) WITH THERAPEUTIC USE
    a) Adverse central nervous system effects reported occasionally during betahistine therapy have included fatigue, lethargy, dizziness, hypersomnolence, and insomnia (Deering et al, 1986).
    B) TREMOR
    1) WITH THERAPEUTIC USE
    a) Muscle twitching or tremors have also been reported (Schmidt & Huizing, 1992).
    C) HEADACHE
    1) WITH THERAPEUTIC USE
    a) Headache has been reported in up to 25% of patients treated with betahistine (Cook & James, 1981).
    D) DROWSY
    1) WITH THERAPEUTIC USE
    a) Drowsiness occurs in approximately 19% of patients treated with oral betahistine (Deering et al, 1986) Fraysse et al, 1991).
    E) LACK OF EFFECT
    1) WITH THERAPEUTIC USE
    a) High doses of betahistine (72 mg three times daily) did not adversely affect psychomotor performance (driving skills) (Betts et al, 1991).

Gastrointestinal

    3.8.2) CLINICAL EFFECTS
    A) GASTROENTERITIS
    1) WITH THERAPEUTIC USE
    a) Gastrointestinal disturbances, including nausea, abdominal pain, or discomfort, diarrhea, and vomiting, have been reported in up to 20% of patients treated with betahistine (Fraysse et al, 1991; (Cook & James, 1981) Elbaz, 1988).

Genitourinary

    3.10.2) CLINICAL EFFECTS
    A) INCREASED FREQUENCY OF URINATION
    1) WITH THERAPEUTIC USE
    a) A significant increase in micturition frequency has been described in some patients treated with oral betahistine (Seipel & Floam, 1975).

Dermatologic

    3.14.2) CLINICAL EFFECTS
    A) ERUPTION
    1) WITH THERAPEUTIC USE
    a) Flushing (Cook & James, 1981; Cochran et al, 1974), skin rash and pruritus (Jimenez et al, 1996) Schmidt & Huizing, 1992) may occur.

Treatment

Life Support

    A) Support respiratory and cardiovascular function.

Oral Exposure

    6.5.1) PREVENTION OF ABSORPTION/PREHOSPITAL
    A) ACTIVATED CHARCOAL
    1) PREHOSPITAL ACTIVATED CHARCOAL ADMINISTRATION
    a) Consider prehospital administration of activated charcoal as an aqueous slurry in patients with a potentially toxic ingestion who are awake and able to protect their airway. Activated charcoal is most effective when administered within one hour of ingestion. Administration in the prehospital setting has the potential to significantly decrease the time from toxin ingestion to activated charcoal administration, although it has not been shown to affect outcome (Alaspaa et al, 2005; Thakore & Murphy, 2002; Spiller & Rogers, 2002).
    1) In patients who are at risk for the abrupt onset of seizures or mental status depression, activated charcoal should not be administered in the prehospital setting, due to the risk of aspiration in the event of spontaneous emesis.
    2) The addition of flavoring agents (cola drinks, chocolate milk, cherry syrup) to activated charcoal improves the palatability for children and may facilitate successful administration (Guenther Skokan et al, 2001; Dagnone et al, 2002).
    2) CHARCOAL DOSE
    a) Use a minimum of 240 milliliters of water per 30 grams charcoal (FDA, 1985). Optimum dose not established; usual dose is 25 to 100 grams in adults and adolescents; 25 to 50 grams in children aged 1 to 12 years (or 0.5 to 1 gram/kilogram body weight) ; and 0.5 to 1 gram/kilogram in infants up to 1 year old (Chyka et al, 2005).
    1) Routine use of a cathartic with activated charcoal is NOT recommended as there is no evidence that cathartics reduce drug absorption and cathartics are known to cause adverse effects such as nausea, vomiting, abdominal cramps, electrolyte imbalances and occasionally hypotension (None Listed, 2004).
    b) ADVERSE EFFECTS/CONTRAINDICATIONS
    1) Complications: emesis, aspiration (Chyka et al, 2005). Aspiration may be complicated by acute respiratory failure, ARDS, bronchiolitis obliterans or chronic lung disease (Golej et al, 2001; Graff et al, 2002; Pollack et al, 1981; Harris & Filandrinos, 1993; Elliot et al, 1989; Rau et al, 1988; Golej et al, 2001; Graff et al, 2002). Refer to the ACTIVATED CHARCOAL/TREATMENT management for further information.
    2) Contraindications: unprotected airway (increases risk/severity of aspiration) , nonfunctioning gastrointestinal tract, uncontrolled vomiting, and ingestion of most hydrocarbons (Chyka et al, 2005).
    6.5.2) PREVENTION OF ABSORPTION
    A) ACTIVATED CHARCOAL
    1) CHARCOAL ADMINISTRATION
    a) Consider administration of activated charcoal after a potentially toxic ingestion (Chyka et al, 2005). Administer charcoal as an aqueous slurry; most effective when administered within one hour of ingestion.
    2) CHARCOAL DOSE
    a) Use a minimum of 240 milliliters of water per 30 grams charcoal (FDA, 1985). Optimum dose not established; usual dose is 25 to 100 grams in adults and adolescents; 25 to 50 grams in children aged 1 to 12 years (or 0.5 to 1 gram/kilogram body weight) ; and 0.5 to 1 gram/kilogram in infants up to 1 year old (Chyka et al, 2005).
    1) Routine use of a cathartic with activated charcoal is NOT recommended as there is no evidence that cathartics reduce drug absorption and cathartics are known to cause adverse effects such as nausea, vomiting, abdominal cramps, electrolyte imbalances and occasionally hypotension (None Listed, 2004).
    b) ADVERSE EFFECTS/CONTRAINDICATIONS
    1) Complications: emesis, aspiration (Chyka et al, 2005). Aspiration may be complicated by acute respiratory failure, ARDS, bronchiolitis obliterans or chronic lung disease (Golej et al, 2001; Graff et al, 2002; Pollack et al, 1981; Harris & Filandrinos, 1993; Elliot et al, 1989; Rau et al, 1988; Golej et al, 2001; Graff et al, 2002). Refer to the ACTIVATED CHARCOAL/TREATMENT management for further information.
    2) Contraindications: unprotected airway (increases risk/severity of aspiration) , nonfunctioning gastrointestinal tract, uncontrolled vomiting, and ingestion of most hydrocarbons (Chyka et al, 2005).
    B) GASTRIC LAVAGE
    1) INDICATIONS: Consider gastric lavage with a large-bore orogastric tube (ADULT: 36 to 40 French or 30 English gauge tube {external diameter 12 to 13.3 mm}; CHILD: 24 to 28 French {diameter 7.8 to 9.3 mm}) after a potentially life threatening ingestion if it can be performed soon after ingestion (generally within 60 minutes).
    a) Consider lavage more than 60 minutes after ingestion of sustained-release formulations and substances known to form bezoars or concretions.
    2) PRECAUTIONS:
    a) SEIZURE CONTROL: Is mandatory prior to gastric lavage.
    b) AIRWAY PROTECTION: Place patients in the head down left lateral decubitus position, with suction available. Patients with depressed mental status should be intubated with a cuffed endotracheal tube prior to lavage.
    3) LAVAGE FLUID:
    a) Use small aliquots of liquid. Lavage with 200 to 300 milliliters warm tap water (preferably 38 degrees Celsius) or saline per wash (in older children or adults) and 10 milliliters/kilogram body weight of normal saline in young children(Vale et al, 2004) and repeat until lavage return is clear.
    b) The volume of lavage return should approximate amount of fluid given to avoid fluid-electrolyte imbalance.
    c) CAUTION: Water should be avoided in young children because of the risk of electrolyte imbalance and water intoxication. Warm fluids avoid the risk of hypothermia in very young children and the elderly.
    4) COMPLICATIONS:
    a) Complications of gastric lavage have included: aspiration pneumonia, hypoxia, hypercapnia, mechanical injury to the throat, esophagus, or stomach, fluid and electrolyte imbalance (Vale, 1997). Combative patients may be at greater risk for complications (Caravati et al, 2001).
    b) Gastric lavage can cause significant morbidity; it should NOT be performed routinely in all poisoned patients (Vale, 1997).
    5) CONTRAINDICATIONS:
    a) Loss of airway protective reflexes or decreased level of consciousness if patient is not intubated, following ingestion of corrosive substances, hydrocarbons (high aspiration potential), patients at risk of hemorrhage or gastrointestinal perforation, or trivial or non-toxic ingestion.
    6.5.3) TREATMENT
    A) ANAPHYLAXIS
    1) SUMMARY
    a) Mild to moderate allergic reactions may be treated with antihistamines with or without inhaled beta adrenergic agonists, corticosteroids or epinephrine. Treatment of severe anaphylaxis also includes oxygen supplementation, aggressive airway management, epinephrine, ECG monitoring, and IV fluids.
    2) BRONCHOSPASM
    a) ALBUTEROL
    1) ADULT: 2.5 to 5 milligrams in 2 to 4.5 milliliters of normal saline delivered per nebulizer every 20 minutes up to 3 doses. If incomplete response administer 2.5 to 10 mg every 1 to 4 hours as needed, or 10 to 15 mg/hr by continuous nebulization as needed (National Heart,Lung,and Blood Institute, 2007). CHILD: 0.15 milligram/kilogram (minimum 2.5 milligrams) per nebulizer every 20 minutes up to 3 doses. If incomplete response administer 0.15 to 0.3 mg/kg (up to 10 mg) every 1 to 4 hours as needed, or 0.5 mg/kg/hr by continuous nebulization (National Heart,Lung,and Blood Institute, 2007).
    3) CORTICOSTEROIDS
    a) Consider systemic corticosteroids in patients with significant bronchospasm.
    b) PREDNISONE: ADULT: 40 to 80 milligrams/day. CHILD: 1 to 2 milligrams/kilogram/day (maximum 60 mg) in 1 to 2 divided doses divided twice daily (National Heart,Lung,and Blood Institute, 2007).
    4) MILD CASES
    a) DIPHENHYDRAMINE
    1) SUMMARY: Oral diphenhydramine, as well as other H1 antihistamines can be used as indicated (Lieberman et al, 2010).
    2) ADULT: 50 milligrams orally, or 10 to 50 mg intravenously at a rate not to exceed 25 mg/min or may be given by deep intramuscular injection. A total of 100 mg may be administered if needed. Maximum daily dosage is 400 mg (Prod Info diphenhydramine HCl intravenous injection solution, intramuscular injection solution, 2013).
    3) CHILD: 5 mg/kg/24 hours or 150 mg/m(2)/24 hours. Divided into 4 doses, administered intravenously at a rate not exceeding 25 mg/min or by deep intramuscular injection. Maximum daily dosage is 300 mg (Prod Info diphenhydramine HCl intravenous injection solution, intramuscular injection solution, 2013).
    5) MODERATE CASES
    a) EPINEPHRINE: INJECTABLE SOLUTION: It should be administered early in patients by IM injection. Using a 1:1000 (1 mg/mL) solution of epinephrine. Initial Dose: 0.01 mg/kg intramuscularly with a maximum dose of 0.5 mg in adults and 0.3 mg in children. The dose may be repeated every 5 to 15 minutes, if no clinical improvement. Most patients respond to 1 or 2 doses (Nowak & Macias, 2014).
    6) SEVERE CASES
    a) EPINEPHRINE
    1) INTRAVENOUS BOLUS: ADULT: 1 mg intravenously as a 1:10,000 (0.1 mg/mL) solution; CHILD: 0.01 mL/kg intravenously to a maximum single dose of 1 mg given as a 1:10,000 (0.1 mg/mL) solution. It can be repeated every 3 to 5 minutes as needed. The dose can also be given by the intraosseous route if IV access cannot be established (Lieberman et al, 2015). ALTERNATIVE ROUTE: ENDOTRACHEAL ADMINISTRATION: If IV/IO access is unavailable. DOSE: ADULT: Administer 2 to 2.5 mg of 1:1000 (1 mg/mL) solution diluted in 5 to 10 mL of sterile water via endotracheal tube. CHILD: DOSE: 0.1 mg/kg to a maximum of 2.5 mg administered as a 1:1000 (1 mg/mL) solution diluted in 5 to 10 mL of sterile water via endotracheal tube (Lieberman et al, 2015).
    2) INTRAVENOUS INFUSION: Intravenous administration may be considered in patients poorly responsive to IM or SubQ epinephrine. An epinephrine infusion may be prepared by adding 1 mg (1 mL of 1:1000 (1 mg/mL) solution) to 250 mL D5W, yielding a concentration of 4 mcg/mL, and infuse this solution IV at a rate of 1 mcg/min to 10 mcg/min (maximum rate). CHILD: A dosage of 0.01 mg/kg (0.1 mL/kg of a 1:10,000 (0.1 mg/mL) solution up to 10 mcg/min (maximum dose 0.3 mg) is recommended for children (Lieberman et al, 2010). Careful titration of a continuous infusion of IV epinephrine, based on the severity of the reaction, along with a crystalloid infusion can be considered in the treatment of anaphylactic shock. It appears to be a reasonable alternative to IV boluses, if the patient is not in cardiac arrest (Vanden Hoek,TL,et al).
    7) AIRWAY MANAGEMENT
    a) OXYGEN: 5 to 10 liters/minute via high flow mask.
    b) INTUBATION: Perform early if any stridor or signs of airway obstruction.
    c) CRICOTHYROTOMY: Use if unable to intubate with complete airway obstruction (Vanden Hoek,TL,et al).
    d) BRONCHODILATORS are recommended for mild to severe bronchospasm.
    e) ALBUTEROL: ADULT: 2.5 to 5 milligrams in 2 to 4.5 milliliters of normal saline delivered per nebulizer every 20 minutes up to 3 doses. If incomplete response administer 2.5 to 10 mg every 1 to 4 hours as needed, or 10 to 15 mg/hr by continuous nebulization as needed (National Heart,Lung,and Blood Institute, 2007).
    f) ALBUTEROL: CHILD: 0.15 milligram/kilogram (minimum 2.5 milligrams) per nebulizer every 20 minutes up to 3 doses. If incomplete response administer 0.15 to 0.3 milligram/kilogram (maximum 10 milligrams) every 1 to 4 hours as needed OR administer 0.5 mg/kg/hr by continuous nebulization (National Heart,Lung,and Blood Institute, 2007).
    8) MONITORING
    a) CARDIAC MONITOR: All complicated cases.
    b) IV ACCESS: Routine in all complicated cases.
    9) HYPOTENSION
    a) If hypotensive give 500 to 2000 milliliters crystalloid initially (20 milliliters/kilogram in children) and titrate to desired effect (stabilization of vital signs, mentation, urine output); adults may require up to 6 to 10 L/24 hours. Central venous or pulmonary artery pressure monitoring is recommended in patients with persistent hypotension.
    1) VASOPRESSORS: Should be used in refractory cases unresponsive to repeated doses of epinephrine and after vigorous intravenous crystalloid rehydration (Lieberman et al, 2010).
    2) DOPAMINE: Initial Dose: 2 to 20 micrograms/kilogram/minute intravenously; titrate to maintain systolic blood pressure greater than 90 mm Hg (Lieberman et al, 2010).
    10) H1 and H2 ANTIHISTAMINES
    a) SUMMARY: Antihistamines are second-line therapy and are used as supportive therapy and should not be used in place of epinephrine (Lieberman et al, 2010).
    1) DIPHENHYDRAMINE: ADULT: 25 to 50 milligrams via a slow intravenous infusion or IM. PEDIATRIC: 1 milligram/kilogram via slow intravenous infusion or IM up to 50 mg in children (Lieberman et al, 2010).
    b) RANITIDINE: ADULT: 1 mg/kg parenterally; CHILD: 12.5 to 50 mg parenterally. If the intravenous route is used, ranitidine should be infused over 10 to 15 minutes or diluted in 5% dextrose to a volume of 20 mL and injected over 5 minutes (Lieberman et al, 2010).
    c) Oral diphenhydramine, as well as other H1 antihistamines, can also be used as indicated (Lieberman et al, 2010).
    11) DYSRHYTHMIAS
    a) Dysrhythmias and cardiac dysfunction may occur primarily or iatrogenically as a result of pharmacologic treatment (epinephrine) (Vanden Hoek,TL,et al). Monitor and correct serum electrolytes, oxygenation and tissue perfusion. Treat with antiarrhythmic agents as indicated.
    12) OTHER THERAPIES
    a) There have been a few reports of patients with anaphylaxis, with or without cardiac arrest, that have responded to vasopressin therapy that did not respond to standard therapy. Although there are no randomized controlled trials, other alternative vasoactive therapies (ie, vasopressin, norepinephrine, methoxamine, and metaraminol) may be considered in patients in cardiac arrest secondary to anaphylaxis that do not respond to epinephrine (Vanden Hoek,TL,et al).
    B) MONITORING OF PATIENT
    1) Monitor blood pressure, respirations, and chest findings regularly.
    C) HYPOTENSIVE EPISODE
    1) SUMMARY
    a) Infuse 10 to 20 milliliters/kilogram of isotonic fluid and keep the patient supine. If hypotension persists, administer dopamine or norepinephrine. Consider central venous pressure monitoring to guide further fluid therapy.
    2) DOPAMINE
    a) DOSE: Begin at 5 micrograms per kilogram per minute progressing in 5 micrograms per kilogram per minute increments as needed (Prod Info dopamine hcl, 5% dextrose IV injection, 2004). If hypotension persists, dopamine may need to be discontinued and a more potent vasoconstrictor (eg, norepinephrine) should be considered (Prod Info dopamine hcl, 5% dextrose IV injection, 2004).
    b) CAUTION: If ventricular dysrhythmias occur, decrease rate of administration (Prod Info dopamine hcl, 5% dextrose IV injection, 2004). Extravasation may cause local tissue necrosis, administration through a central venous catheter is preferred (Prod Info dopamine hcl, 5% dextrose IV injection, 2004).
    3) NOREPINEPHRINE
    a) PREPARATION: 4 milligrams (1 amp) added to 1000 milliliters of diluent provides a concentration of 4 micrograms/milliliter of norepinephrine base. Norepinephrine bitartrate should be mixed in dextrose solutions (dextrose 5% in water, dextrose 5% in saline) since dextrose-containing solutions protect against excessive oxidation and subsequent potency loss. Administration in saline alone is not recommended (Prod Info norepinephrine bitartrate injection, 2005).
    b) DOSE
    1) ADULT: Dose range: 0.1 to 0.5 microgram/kilogram/minute (eg, 70 kg adult 7 to 35 mcg/min); titrate to maintain adequate blood pressure (Peberdy et al, 2010).
    2) CHILD: Dose range: 0.1 to 2 micrograms/kilogram/minute; titrate to maintain adequate blood pressure (Kleinman et al, 2010).
    3) CAUTION: Extravasation may cause local tissue ischemia, administration by central venous catheter is advised (Peberdy et al, 2010).

Range Of Toxicity

Summary

    A) Doses up to 216 milligrams/day have been well tolerated by adults.

Therapeutic Dose

    7.2.1) ADULT
    A) DISEASE STATE
    1) MENIERE'S DISEASE -
    a) In MENIERE's disease and other audiovestibular disorders, betahistine has been given in doses of 8 to 16 milligrams orally 3 times daily (total, 24 to 48 milligrams/day) (Fraysse et al, 1991; (JEF Reynolds , 2000).
    b) Doses of 24 milligrams 3 times daily have also been reported (Deering et al, 1986).
    2) CEREBROVASCULAR DISEASE -
    a) Oral doses of 8 to 16 milligrams 3 times daily have been used in patients with cerebrovascular disease (Cook & James, 1981).

Minimum Lethal Exposure

    A) GENERAL/SUMMARY
    1) No ingestions of betahistine resulting in death have been reported.

Maximum Tolerated Exposure

    A) GENERAL/SUMMARY
    1) The largest one time dose reported is 72 milligrams while the largest daily dose reported is 216 milligrams (Betts et al, 1991). No unexpected adverse results were reported.

Toxicity Information

    7.7.1) TOXICITY VALUES
    A) ANIMAL DATA
    1) LD50- (INTRAPERITONEAL)MOUSE:
    a) 320 mg/kg (RTECS, 2000)
    2) LD50- (ORAL)MOUSE:
    a) 2920 mg/kg (RTECS, 2000)
    3) LD50- (INTRAPERITONEAL)RAT:
    a) 980 mg/kg (RTECS, 2000)
    4) LD50- (ORAL)RAT:
    a) 6110 mg/kg (RTECS, 2000)

References

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