Meclizine

General

• Type: Antihistamine, H1 antagonist
• Dosage Forms: 12.5, 25, 32mg oral tablet; 25mg oral chewable tablet
• Common Trade Names: Univert, Vertin-32, Dramamine less drowsy, Motion-Time

Adult Dosing

Vertigo

• 25mg PO QID

Motion sickness

• 25-100mg PO 1 hour before activity. May repeat q24h

Pediatric Dosing

• >= 12 yrs old: Adult dosing
• < 12 yrs: No dosing specified in drug insert

Special Populations

• Pregnancy Rating: B
• Lactation: Excretion in breast milk unknown
• Renal Dosing: n/a
• Hepatic Dosing: n/a

Contraindications

• Allergy to class/drug

Adverse Reactions

Serious

• CNS depression
• Caution in asthma, glaucoma, BPH, pyloric obstruction

Common

• Drowsiness, fatigue

Pharmacology

• Onset: 1 hour
• Half-life: 5 hours
• Metabolism: Hepatic
• Excretion: Urine and feces
• Mechanism of Action: Central anticholinergic; blocks chemoreceptor trigger zone. Decreases middle ear excitability, blocks vestibular-cerebellar pathways

See Also

• Antihistamines
• Anticholinergic toxicity

References

Lexicomp