Pronunciation:
(MEK li zeen)
U.S. Brand Names:
Antivert®; Bonine® [OTC]; Dramamine® Less Drowsy Formula [OTC]
Synonyms:
Meclizine Hydrochloride; Meclozine Hydrochloride
Generic Available:
Yes
Canadian Brand Names:
Antivert®; Bonamine™; Bonine®
Use:
Prevention and treatment of symptoms of motion sickness; management of vertigo with diseases affecting the vestibular system
Pregnancy Risk Factor:
B
Pregnancy Implications:
No data available on crossing the placenta. Probably no effect on the fetus (insufficient data). Available evidence suggests safe use during pregnancy.
Lactation:
Excretion in breast milk unknown/not recommended
Contraindications:
Hypersensitivity to meclizine or any component of the formulation
Warnings/Precautions:
Use with caution in patients with angle-closure glaucoma, prostatic hyperplasia, pyloric or duodenal obstruction, or bladder neck obstruction; use with caution in hot weather, and during exercise; elderly may be at risk for anticholinergic side effects such as glaucoma, prostatic hyperplasia, constipation, gastrointestinal obstructive disease; if vertigo does not respond in 1-2 weeks, it is advised to discontinue use
Adverse Reactions:
>10%:
Central nervous system: Slight to moderate drowsiness
Respiratory: Thickening of bronchial secretions
1% to 10%:
Central nervous system: Headache, fatigue, nervousness, dizziness
Gastrointestinal: Appetite increase, weight gain, nausea, diarrhea, abdominal pain, xerostomia
Neuromuscular & skeletal: Arthralgia
Respiratory: Pharyngitis
<1%: Palpitations, hypotension, depression, sedation, photosensitivity, rash, angioedema, urinary retention, hepatitis, myalgia, tremor, paresthesia, blurred vision, bronchospasm, epistaxis
Overdosage/Toxicology:
Symptoms of overdose include CNS depression, confusion, nervousness, hallucinations, dizziness, blurred vision, nausea, vomiting, and hyperthermia. There is no specific treatment for antihistamine overdose. Clinical toxicity is due to blockade of cholinergic receptors. For anticholinergic overdose with severe life-threatening symptoms, physostigmine 1-2 mg I.V. slowly, may be given to reverse these effects.
Drug Interactions:
Increased toxicity: CNS depressants, neuroleptics, anticholinergics
Ethanol/Nutrition/Herb Interactions:
Ethanol: Avoid ethanol (may increase CNS depression).
Mechanism of Action:
Has central anticholinergic action by blocking chemoreceptor trigger zone; decreases excitability of the middle ear labyrinth and blocks conduction in the middle ear vestibular-cerebellar pathways
Pharmacodynamics/Kinetics:
Onset of action: ~1 hour
Duration: 8-24 hours
Metabolism: Hepatic
Half-life elimination: 6 hours
Excretion: Urine (as metabolites); feces (as unchanged drug)
Dosage:
Children >12 years and Adults: Oral:
Motion sickness: 12.5-25 mg 1 hour before travel, repeat dose every 12-24 hours if needed; doses up to 50 mg may be needed
Vertigo: 25-100 mg/day in divided doses
Patient Education:
Take exactly as prescribed; do not increase dose. Avoid alcohol, other CNS depressants, sleeping aids without consulting prescriber. You may experience dizziness, drowsiness, or blurred vision (use caution when driving or engaging in tasks that require alertness until response to drug is known); dry mouth (frequent mouth care, sucking lozenges, or chewing gum may help); constipation (increased exercise, fluids, fruit, or may help); or heat intolerance (avoid excessive exercise, hot environments, maintain adequate hydration). Report CNS change (hallucination, confusion, nervousness); sudden or unusual weight gain; unresolved nausea or diarrhea; chest pain or palpitations; muscle pain; or changes in urinary pattern. Breast-feeding precaution: Breast-feeding is not recommended.
Dental Health: Effects on Dental Treatment:
Key adverse event(s) related to dental treatment: Slight to moderate drowsiness, thickening of bronchial secretions, significant xerostomia (normal salivary flow resumes upon discontinuation).
Dental Health: Vasoconstrictor/Local Anesthetic Precautions:
No information available to require special precautions
Mental Health: Effects on Mental Status:
Drowsiness is common; may cause dizziness or nervousness; may rarely cause sedation or depression
Mental Health: Effects on Psychiatric Treatment:
Concurrent use with psychotropic may produce additive sedation and dry mouth
Dosage Forms:
Tablet, as hydrochloride: 12.5 mg, 25 mg
Antivert®: 12.5 mg, 25 mg, 50 mg
Dramamine® Less Drowsy Formula: 25 mg
Tablet, chewable, as hydrochloride (Bonine®): 25 mg
International Brand Names:
Antivert® (CA); Bonamine™ (CA); Bonine® (CA)
References
Oosterveld WJ, "Vertigo: Current Concepts in Management,"Drugs, 1985, 30(3):275-83.
Park J, Logan R, and Pottage A, "Drug-Induced Extrapyramidal Signs in Chronic Liver Disease - A Case Report,"Clin Toxicol, 1977, 11(1):117-20.