meclizine (Antivert, Bonine, Meni D, meclozine, Dramamine Less Drowsy Formula, VertiCalm)

Dosing and uses of Antivert, Bonine (meclizine)

• Adult
• Pediatric

 

Adult dosage forms and strengths

tablet

• 12.5mg
• 25mg
• 32mg

tablet, chewable

• 25mg

 

Motion Sickness

12.5-50 mg PO given 1 hour before travel and then every 24 hr PRn

 

Vertigo

25-100 mg/day PO in single daily dose or divided q6-12hr

 

Pediatric dosage forms and strengths

tablet

• 12.5mg
• 25mg
• 32mg
• 50mg

tablet, chewable

• 25mg

 

Motion Sickness

<12 years: Safety and efficacy not established

>12 years: 12.5-50 mg PO given 1 hour before travel and then daily PRn

 

Vertigo

<12 years: Safety and efficacy not established

>12 years: 25-100 mg/day PO in single daily dose or divided q6-12hr

 

Antivert, Bonine (meclizine) adverse (side) effects

Frequency not defined

Drowsiness

Thickening of bronchial secretions

Acute glaucoma attack

Blurred vision (rare)

Constipation

Fatigue

Vomiting

Xerostomia

Headache

Dry mouth

Urinary retention

 

Warnings

Contraindications

Hypersensitivity

 

Cautions

Use cautioin in obstructive genitourinary tract disease, asthma, pyloric or duodenal obstruction, prostatic hyperplasia, narrow angle glaucoma

Hepatic impairment may increase meclizine systemic exposure

Renal impairment may increase meclizine or metabolite accumulation

May impair physical or mental abilities; use caution when operating heavy machinery or performing tasks which require mental alertness

 

Pregnancy and lactation

Pregnancy category: B

Lactation: Not known if excreted in milk; use caution

 

Pregnancy categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

 

Pharmacology of Antivert, Bonine (meclizine)

Mechanism of action

Antihistamine with activity against nebulized histamine; blocks vasodepressor response to histamine, with slight blocking action against acetylcholine

 

Absorption

Onset: 30-60 min 

Duration: 12-24 hr 

Peak plasma time: 3 hr 

 

Distribution

Vd: 7 L/kg 

 

Metabolism

In vitro study found CYP2D6 the dominant metabolic enzyme

 

Elimination

Half-life: 5 hr

Excretion: Urine, feces

 

Pharmacogenomics

Genetic polymorphism of CYP2D6 that results in extensive-, poor-, intermediate- and ultrarapid metabolizer phenotypes could contribute to large interindividual variability in meclizine exposure