Antagonizes the effects of histamine at H1- receptor sites; does not bind to or inactivate histamine. Significant CNS depressant and anticholinergic properties.
Therapeutic Effect(s):
Decreased symptoms of histamine excess (sneezing, rhinorrhea, nasal/ocular pruritus, ocular tearing/redness and skin itching/urticaria).
Absorption: Well absorbed following oral administration.
Distribution: Unknown.
Metabolism and Excretion: Extensively metabolized by the liver. Inactive metabolites excreted in urine; Negligible renal elimination of unchanged drug.
Begin with lowest dose and ↑ as needed and tolerated. Dose is based on condition severity and response.
PO Administer twice daily.
Use a calibrated measuring device for accurate dose; household tablespoon is not accurate and could lead to overdose. May be fatal if administered to children <2 yr. Shake well before using.
Explain purpose and side effects of medication. Advise patient to read Patient Information before starting therapy.
Advise patient to notify health care provider of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care provider before taking other medications.
Advise patient to avoid taking alcohol or other CNS depressants concurrently with this drug, may cause overdose.
May cause dizziness and drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known
Advise patient that good oral hygiene, frequent rinsing of mouth with water, and sugarless gum or candy may minimize dry mouth. Patient should notify dentist if dry mouth persists >2 wk
Advise patient to notify health care provider if they have ↑ intraocular pressure, narrow angle glaucoma, hyperthyroidism, cardiovascular disease, hypertension, peptic ulcer, prostatic hypertrophy, or bladder neck obstruction.
Rep: Instruct women of reproductive potential to notify health care provider if pregnancy is planned or suspected and avoid breastfeeding during therapy.