HYDROXYZINE HYDROCHLORIDE

Hydroxyzine hydrochloride has the chemical name of 2-[2-[4-( p -Chloro-α-phenylbenzyl)-1-piperazinyl] ethoxy] ethanol dihydrochloride. C 21 H 27 ClN 2 O 2 •2HCl Molecular Weight 447.83 Hydroxyzine hydrochloride USP occurs as a white powder which is very soluble in water. Each tablet for oral administration contains 10 mg, 25 mg or 50 mg hydroxyzine hydrochloride USP. Inactive ingredients include FD&C blue #2 aluminum lake, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, pregelatinized starch (corn), and titanium dioxide. In addition, 10 mg contains D&C red #30 aluminum lake, 25 mg and 50 mg contains D&C red #7 calcium lake. CHEMICAL STRUCTURE

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested. Useful in the management of pruritus due to allergic conditions such as chronic urticaria and atopic and contact dermatoses and in histamine-mediated pruritus. As a sedative when used as a premedication and following general anesthesia, hydroxyzine may potentiate meperidine and barbiturates , so their use in pre-anesthetic adjunctive therapy should be modified on an individual basis. Atropine and other belladonna alkaloids are not affected by the drug. Hydroxyzine is not known to interfere with the action of digitalis in any way and it may be used concurrently with this agent. The effectiveness of hydroxyzine as an antianxiety agent for long term use, that is more than 4 months, has not been assessed by systematic clinical studies. The physician should reassess periodically the usefulness of the drug for the individual patient.

For symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested: adults, 50 to 100 mg q.i.d.; children under 6 years, 50 mg daily in divided doses; children over 6 years, 50 to 100 mg daily in divided doses. For use in the management of pruritus due to allergic conditions such as chronic urticaria and atopic and contact dermatoses and in histamine-mediated pruritus: adults, 25 mg t.i.d. or q.i.d.; children under 6 years, 50 mg daily in divided doses; children over 6 years, 50 to 100 mg daily in divided doses. As a sedative when used as a premedication and following general anesthesia: 50 to 100 mg for adults and 0.6 mg/kg of body weight in children. When treatment is initiated by the intramuscular route of administration, subsequent doses may be administered orally. As with all potent medication, the dosage should be adjusted according to the patient's response to therapy.

Oral hydroxyzine hydrochloride is contraindicated in patients with known hypersensitivity to hydroxyzine hydrochloride products, and in patients with known hypersensitivity to cetirizine hydrochloride or levocetirizine hydrochloride. Hydroxyzine is contraindicated in patients with a prolonged QT interval. Hydroxyzine, when administered to the pregnant mouse, rat, and rabbit induced fetal abnormalities in the rat and mouse at doses substantially above the human therapeutic range. Clinical data in human beings are inadequate to establish safety in early pregnancy. Until such data are available, hydroxyzine is contraindicated in early pregnancy. Hydroxyzine is contraindicated for patients who have shown a previous hypersensitivity to any component of this medication.

Side effects reported with the administration of hydroxyzine hydrochloride are usually mild and transitory in nature. Anticholinergic: Dry mouth. Central Nervous System: Drowsiness is usually transitory and may disappear in a few days of continued therapy or upon reduction of dose. Involuntary motor activity including rare instances of tremor and convulsions have been reported, usually with doses considerably higher than those recommended. Clinically significant respiratory depression has not been reported at recommended doses. Cardiac System: QT prolongation, Torsade de Pointes. In postmarketing experience, the following additional undesirable effects have been reported: Body as a Whole: Allergic reaction. Nervous System: Headache. Psychiatric: Hallucination. Skin and Appendages: Oral hydroxyzine is associated with Acute Generalized Exanthematous Pustulosis (AGEP) and fixed drug eruptions in post marketing reports; pruritus, rash, urticaria.