hydroxyzine

hydroxyzine

(hye drox' i zeen)

hydroxyzine hydrochloride

Oral preparations:

Apo-Hydroxyzine (CAN), Novo-Hydroxyzine (CAN), Vistaril

Parenteral preparations:

Vistaril

hydroxyzine pamoate

Oral preparations:

Vistaril

Pregnancy Category C

Drug classes

Anxiolytic

Antihistamine

Antiemetic

Therapeutic actions

Mechanisms of action not understood; actions may be due to suppression of subcortical areas of the CNS; has clinically demonstrated antihistaminic, analgesic, antispasmodic, antiemetic, mild antisecretory, and bronchodilator activity

Indications

·        Symptomatic relief of anxiety and tension associated with psychoneurosis; adjunct in organic disease states in which anxiety is manifested; alcoholism and asthma; before dental procedures

·        Management of pruritus due to allergic conditions, such as chronic urticaria, atopic and contact dermatosis, and in histamine-mediated pruritus

·        Sedation when used as premedication and following general anesthesia

·        Control of nausea and vomiting and as adjunct to analgesia preoperatively and postoperatively (parenteral) to allow decreased opioid dosage

·        IM administration: Management of the acutely disturbed or hysterical patient; the acute or chronic alcoholic with anxiety withdrawal symptoms or delirium tremens; as preoperative and postoperative and prepartum and postpartum adjunctive medication to permit reduction in narcotic dosage, allay anxiety, and control emesis

Contraindications and cautions

·        Contraindicated with allergy to hydroxyzine, pregnancy, lactation.

·        Use cautiously with uncomplicated vomiting in children (may contribute to Reye's syndrome or unfavorably influence its outcome; extrapyramidal effects may obscure diagnosis of Reye's syndrome).

Available forms

Tablets—10, 25, 50, 100 mg; syrup—10 mg/5 mL; capsules—25, 50, 100 mg; oral suspension—25 mg/5 mL; injection—25, 50 mg/mL

Dosages

Start patients on IM therapy when indicated; use oral therapy for maintenance. Adjust dosage to patient's response.

ADULTS

Oral

·        Symptomatic relief of anxiety: 50–100 mg qid.

·        Management of pruritus: 25 mg tid–qid.

·        Sedative (preoperative and postoperative): 50–100 mg.

IM

·        Psychiatric and emotional emergencies, including alcoholism: 50–100 mg immediately and q 4–6 hr as needed.

·        Nausea and vomiting: 25–100 mg.

·        Preoperative and postoperative, prepartum and postpartum: 25–100 mg.

PEDIATRIC PATIENTS

Oral

·        Anxiety, pruritus:
< 6 yr: 50 mg/day in divided doses.
> 6 yr: 50–100 mg/day in divided doses.

·        Sedative: 0.6 mg/kg.

IM

·        Nausea, preoperative and postoperative: 1.1 mg/kg (0.5 mg/lb).

Pharmacokinetics

Route	Onset	Peak	Duration
Oral, IM	15–30 min	3 hr	4–6 hr

Metabolism: Hepatic; T_1/2: 3 hr

Distribution: Crosses placenta; may enter breast milk

Excretion: Urine

Adverse effects

·        CNS: Drowsiness, involuntary motor activity, including tremor and seizures

·        GI: Dry mouth, reflux, constipation

·        GU: Urinary retention

·        Hypersensitivity: Wheezing, dyspnea, chest tightness

Interactions

Drug-drug

·        Potentiating action when used concomitantly with CNS depressants (opioids, barbiturates)

Nursing considerations

Assessment

·        History: Allergy to hydroxyzine or cetirizine, uncomplicated vomiting in children, lactation, pregnancy

·        Physical: Skin color, lesions, texture; orientation, reflexes, affect; R, adventitious sounds

Interventions

·        WARNING: Determine and treat underlying cause of vomiting. Drug may mask signs and symptoms of serious conditions, such as brain tumor, intestinal obstruction, appendicitis.

·        Do not administer parenteral solution subcutaneously, IV, or intra-arterially; tissue necrosis has occurred with subcutaneous and intra-arterial injection, and hemolysis with IV injection.

·        Give IM injections deep into a large muscle. In adults, use upper outer quadrant of buttocks or midlateral thigh; in children use midlateral thigh muscles; use deltoid area only if well developed.

Teaching points

·        Take this drug as prescribed. Avoid excessive dosage.

·        You may experience these side effects: Dizziness, sedation, drowsiness (use caution if driving or performing tasks that require alertness); avoid alcohol, sedatives, sleep aids (serious overdosage could result); dry mouth (frequent mouth care, sucking on sugarless lozenges may help).

·        Report difficulty breathing, tremors, loss of coordination, sore muscles, or muscle spasms.

Adverse effects in Italic are most common; those in Bold are life-threatening.