2.1 Recommended Dosage

The recommended dosage is 25 mg to 100 mg daily administered orally, in divided doses, depending upon clinical response.

2.2 Administration Instructions

Tablets

• 12.5 mg: Pink mottled, round shaped, biconvex tablets, debossed with 'I50' on one side and plain on other side.
• 25 mg: Pink mottled, round shaped, biconvex tablets, debossed with 'I60' on one side and plain on other side.
• 50 mg: Pink mottled, oval shaped, biconvex tablets, debossed with 'I171' on one side and partial breakline on other side.

5.1 Drowsiness

Since drowsiness may occur with use of meclizine hydrochloride tablets, patients should be warned of this possibility and cautioned against driving a car or operating dangerous machinery.

Patients should avoid alcoholic beverages while taking meclizine hydrochloride tablets [see Drug Interactions (7.1)].

5.2 Concurrent Medical Conditions

Because of its potential anticholinergic action, meclizine hydrochloride tablets should be used with caution in patients with asthma, glaucoma, or enlargement of the prostate gland.

7.1 CNS Depressants

There may be increased CNS depression when meclizine hydrochloride tablets are administered concurrently with other CNS depressants, including alcohol [see Warnings and Precautions (5.1)].

7.2 CYP2D6 Inhibitors

Based on in-vitro evaluation, meclizine is metabolized by CYP2D6. Therefore, there is a possibility for a drug interaction between meclizine hydrochloride tablets and CYP2D6 inhibitors. Therefore, monitor for adverse reactions and clinical effect accordingly.

8.1 Pregnancy

8.2 Lactation

8.4 Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

8.5 Geriatric Use

In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

8.6 Hepatic Impairment

The effect of hepatic impairment on the pharmacokinetics of meclizine has not been evaluated. As meclizine hydrochloride tablets undergo metabolism, hepatic impairment may result in increased systemic exposure of meclizine. Treatment with meclizine hydrochloride tablets should be administered with caution in patients with hepatic impairment.

8.7 Renal Impairment

The effect of renal impairment on the pharmacokinetics of meclizine has not been evaluated. Because of a potential for drug/metabolite accumulation, meclizine hydrochloride tablets should be administered with caution in patients with renal impairment and in the elderly, as renal function generally declines with age.

8.8 Genetic CYP2D6 Polymorphism

The genetic polymorphism of CYP2D6 that results in poor-, intermediate-, extensive-, and ultrarapid metabolizer phenotypes could contribute to large inter-individual variability in meclizine exposure. Therefore, when meclizine hydrochloride tablets are administered to patients with CYP2D6 polymorphism, monitor for adverse reactions and clinical effect accordingly.

Tablets

Inactive ingredients for the tablets are: colloidal silicon dioxide; lactose monohydrate; magnesium stearate; microcrystalline cellulose; sodium starch glycolate; corn starch; FD&C Red # 40.

Each meclizine hydrochloride 12.5 mg tablet contains 12.5 mg of meclizine dihydrochloride equivalent to10.53 mg of meclizine free base.

Each meclizine hydrochloride 25 mg tablet contains 25 mg of meclizine dihydrochloride equivalent to 21.07 mg of meclizine free base.

Each meclizine hydrochloride 50 mg tablet contains 50 mg of meclizine dihydrochloride equivalent to 42.14 mg of meclizine free base.

12.1 Mechanism of Action

The precise mechanism by which meclizine exerts its therapeutic effect is unknown but is presumed to involve antagonism of the histamine H1 receptor.

12.2 Pharmacodynamics

There are no relevant pharmacodynamic data regarding meclizine.

12.3 Pharmacokinetics

The available pharmacokinetic information for meclizine following oral administration has been summarized from published literature.

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

16.1 How Supplied

16.2 Storage and Handling

Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C (59°F and 86°F) [See USP Controlled Room Temperature]. Dispense in a tight, light-resistant container (USP).

Administration Instructions

Advise patients that the tablets must be swallowed whole, but chewable tablets must be chewed or crushed completely before swallowing [see Dosage and Administration (2.1)].

Adverse Reactions

Advise patients that meclizine hydrochloride tablets may cause anaphylactic reaction, drowsiness, dry mouth, headache, fatigue, vomiting and, on rare occasions, blurred vision [see Warnings and Precautions (5.1), Adverse Reactions (6)].

Inform patients that meclizine hydrochloride tablets may impair their ability to engage in potentially dangerous activities, such as operating machinery or vehicles.

Concomitant Drug Interactions

Advise patients regarding medications that should not be taken in combination with meclizine hydrochloride tablets or that may necessitate increased monitoring [see Drug Interactions (7.1, 7.2)]. Inform patients that alcohol may increase adverse reactions.

Concurrent Medical Conditions

Advise patients to notify their healthcare provider about all of their medical conditions, including if they are pregnant or plan to become pregnant or if they are breastfeeding [see Warnings and Precautions (5.2), Use in Specific Populations (8.1, 8.2)].