home > drugs a-z list > clemastine fumarate syrup (clemastine fumarate syrup) drug center > clemastine fumarate syrup (clemastine fumarate syrup) drug - warnings and precautions

Antihistamines should be used with considerable caution in patients with: narrow angle glaucoma, stenosing peptic ulcer, pyloroduodenal obstruction, symptomatic prostatic hypertrophy, and bladder neck obstruction.

Use with CNS Depressants

Clemastine has additive effects with alcohol and other CNS depressants (hypnotics, sedatives, tranquilizers, etc.).

Use in Activities Requiring Mental Alertness

Patients should be warned about engaging in activities requiring mental alertness such as driving a car or operating appliances, machinery, etc.

Use in the Elderly (approximately 60 years or older)

Antihistamines are more likely to cause dizziness, sedation, and hypotension in elderly patients.

General

Clemastine fumarate should be used with caution in patients with: history of bronchial asthma, increased intraocular pressure, hyperthyroidism, cardiovascular disease, and hypertension.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Pregnancy

Teratogenic Effects

Nursing Mothers

Although quantitative determinations of antihistaminic drugs in breast milk have not been reported, qualitative tests have documented the excretion of diphenhydramine, pyrilamine, and tripelennamine in human milk.

Because of the potential for adverse reactions in nursing infants from antihistamines, a decision should be made whether to discontinue nursing or to discontinue the drug.

Pediatric Use

The safety and efficacy of Clemastine Fumarate Syrup has been confirmed in the pediatric population (age 6 years through 12). Safety and dose tolerance studies have confirmed pediatric patients 6 through 11 years tolerated dosage ranges of 0.75 to 2.25 mg clemastine. In pediatric patients particularly, antihistamines in overdosage may produce hallucinations, convulsions and death. Symptoms of antihistamine toxicity in pediatric patients may include fixed dilated pupils, flushed face, dry mouth, fever, excitation, hallucinations, ataxia, incoordination, athetosis, tonic-clonic convulsions, and postictal depression (see OVERDOSAGE).

Carcinogenesis, Mutagenesis, Impairment of Fertility

Pregnancy

Teratogenic Effects

Nursing Mothers

Although quantitative determinations of antihistaminic drugs in breast milk have not been reported, qualitative tests have documented the excretion of diphenhydramine, pyrilamine, and tripelennamine in human milk.

Because of the potential for adverse reactions in nursing infants from antihistamines, a decision should be made whether to discontinue nursing or to discontinue the drug.

Pediatric Use

The safety and efficacy of Clemastine Fumarate Syrup has been confirmed in the pediatric population (age 6 years through 12). Safety and dose tolerance studies have confirmed pediatric patients 6 through 11 years tolerated dosage ranges of 0.75 to 2.25 mg clemastine. In pediatric patients particularly, antihistamines in overdosage may produce hallucinations, convulsions and death. Symptoms of antihistamine toxicity in pediatric patients may include fixed dilated pupils, flushed face, dry mouth, fever, excitation, hallucinations, ataxia, incoordination, athetosis, tonic-clonic convulsions, and postictal depression (see OVERDOSAGE).

Last reviewed on RxList: 8/11/2008
This monograph has been modified to include the generic and brand name in many instances.