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meclizine hydrochloride (meclozine (UK))
Pharmacologic class: Anticholinergic
Therapeutic class: Antiemetic, antivertigo drug
Pregnancy risk category B
Decreases excitability of middle-ear labyrinth and depresses conduction in vestibular-cerebellar pathways
Tablets: 12.5 mg, 25 mg, 50 mg
Tablets (chewable): 25 mg
Indications and dosages
➣ Motion sickness
Adults: 25 to 50 mg P.O. 1 hour before travel. May repeat q 24 hours for duration of travel.
➣ Vertigo associated with diseases affecting the vestibular system
Adults: 25 to 100 mg P.O. daily in divided doses
• Hypersensitivity to drug
Use cautiously in:
• prostatic hypertrophy, stenosing peptic ulcer, bladder neck obstruction, pyloroduodenal obstruction, arrhythmias, angle-closure glaucoma, bronchial asthma
• pregnant or breastfeeding patients
• children (younger than age 12).
• Know that tablets may be chewed or swallowed whole.
CNS: drowsiness, fatigue, confusion, excitement, euphoria, nervousness, restlessness, insomnia, vertigo, visual and auditory hallucinations, seizures
CV: hypotension, palpitations, tachycardia
EENT: blurred vision, diplopia, tinnitus, dry nose, dry throat
GI: nausea, vomiting, diarrhea, constipation, dry mouth, anorexia
GU: difficulty urinating, urinary retention, urinary frequency
Skin: rash, urticaria
Drug-drug. Anticholinergics (including some antihistamines, antidepressants, atropine, haloperidol, phenothiazines): additive anticholinergic effects
Antihistamines, CNS depressants (such as opioids, sedative-hypnotics): additive CNS depression
Drug-diagnostic tests. Skin tests using allergen extracts: false-negative results
Drug-behaviors. Alcohol use: additive CNS depression
• Discontinue drug, as ordered, at least 4 days before skin testing.
• Know that drug has anticholinergic effects.
• Tell patient to take as prescribed to minimize adverse effects.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• Advise patient to relieve dry mouth with hard candy or frequent sips of fluids.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.