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 increase as needed and tolerated. Dose is based on condition severity and patient 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 under 2 yr.Shake well before using.
May cause dizziness and drowsiness. Caution patient to avoid driving or other activities requiring alertness until response to medication is known
Advise patient to avoid taking alcohol or other CNS depressants concurrently with this drug, may cause overdose.
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
Rep: Instruct females of reproductive potential to notify health care professional if pregnancy is planned or suspected and avoid breastfeeding during therapy.