Names and pronunciation
(hye-drox′i-zeen) Atarax , Vistaril
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Drug reference
(hye-drox′i-zeen) Atarax , Vistaril
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Func. class.: Antianxiety/antihista- mine/sedative/hypnotic, antiemetic
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Chem. class.: Piperazine derivative
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Do not confuse: hydrOXYzine/hydrALAZINE
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ACTION: Depresses subcortical levels of CNS, including limbic system, reticular formation; competes with H1-receptor sites
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USES: Anxiety preoperatively, preven- tion of nausea, vomiting postoperatively; to potentiate opioid analgesics; sedation; pruritus
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CONTRAINDICATIONS: Preg- nancy 1st trimester, breastfeeding; hyper- sensitivity to this product or cetirizine; acute asthma Precautions: Pregnancy (2nd/3rd trimes- ter), geriatric patients, debilitated patients, renal/hepatic disease, closed-angle glau- coma, COPD, prostatic hypertrophy, asthma
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SIDE EFFECTS CNS: Dizziness, drowsiness, confusion, headache, tremors, fatigue, depression, seizures CV: Hypotension GI: Dry mouth, increased appetite, nau- sea, diarrhea, weight gain
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INTERACTIONS Increase: CNS depressant effect—bar- biturates, opioids, analgesics, alcohol, sedative/hypnotics, other CNS depressants Increase: anticholinergic effects—phe- nothiazines, quiNIDine, disopyramide, antihistamines, antidepressants, atro- pine, haloperidol, MAOIs Drug/Lab Test False negative: skin allergy testing False increase: 17-hydroxycorticosteroids
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TREATMENT OF OVERDOSE: Lavage if orally ingested; VS, supportive care; IV norepinephrine for hypotension
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DOSAGE AND ROUTES Anxiety • Adult: PO 50-100 mg qid, max 400 mg/day; IM 50-100 mg q4-6hr • Child ≥6 yr: PO 50-100 mg/day in divided doses, max 100 mg/day or 2 mg/ kg/day • Child <6 yr: PO 50 mg/day in divided doses, max 50 mg/day or 2 mg/kg/day Alcohol withdrawal • Adult: IM 50-100 mg q4-6hr Preoperatively/postoperatively (nausea/vomiting) • Adult: IM 25-100 mg q4-6hr • Child: IM 1.1 mg/kg as a single dose Pruritus • Adult: PO 25 mg tid-qid; IM 50-100 mg, then q4-6hr prn, switch to PO as soon as feasible • Child ≥6 yr: PO 50-100 mg/day in divided doses; IM 0.5-1 mg/kg/dose q4- 6hr prn, use PO when possible • Child <6 yr: PO 50 mg/day in divided doses Renal dose • Adult: PO CCr <50 mL/min, give 50% of dose
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Available forms: Tabs 10, 25, 50 mg; caps 25, 50, 100 mg; syrup 2 mg/mL , 10 mg/5 mL; inj 25, 50 mg/mL; oral susp 25 mg/5 mL
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Administer: PO route • Without regard to meals • Crushed if patient is unable to swallow medication whole • Shake oral susp before giving IM route • Does not need to be diluted; give by Z-track inj in large muscle to decrease pain, chance of necrosis; never give IV/ SUBCUT (HCl)
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Assess: • Anticholinergic effects: dry mouth, dizziness, confusion, hypotension, in- creased sedation; monitor B/P • Assistance with ambulation during be- ginning therapy, since drowsiness, dizzi- ness occurs • Beers: avoid use in older adults; anti- cholinergic effects, toxicity may occur • Pregnancy/breastfeeding: do not use in pregnancy/breastfeeding
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Evaluate: • Therapeutic response: decreased anxiety
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CLINICAL CONSIDERATIONS
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Patient and caregiver information: • To avoid OTC preparations (cold, cough, hay fever) unless approved by prescriber • To avoid driving, activities that require alertness • To avoid alcohol, psychotropic medi- cations • Not to discontinue medication quickly after long-term use • To rise slowly because fainting may occur • To report urinary retention, constipa- tion, or other serious anticholinergic symptoms to provider, discontinue use
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PHARMACOKINETICS PO: Onset 15-60 min, duration 4-6 hr, half-life 3 hr, metabolized by liver, excreted by kidneys
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• Adult: PO 50-100 mg qid, max 400 mg/day; IM 50-100 mg q4-6hr
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• Child ≥6 yr: PO 50-100 mg/day in divided doses, max 100 mg/day or 2 mg/ kg/day
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• Child <6 yr: PO 50 mg/day in divided doses, max 50 mg/day or 2 mg/kg/day Alcohol withdrawal
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• Adult: IM 50-100 mg q4-6hr Preoperatively/postoperatively (nausea/vomiting)
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• Adult: IM 25-100 mg q4-6hr
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• Child: IM 1.1 mg/kg as a single dose Pruritus
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• Adult: PO 25 mg tid-qid; IM 50-100 mg, then q4-6hr prn, switch to PO as soon as feasible
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• Child ≥6 yr: PO 50-100 mg/day in divided doses; IM 0.5-1 mg/kg/dose q4- 6hr prn, use PO when possible
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• Child <6 yr: PO 50 mg/day in divided doses Renal dose
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• Adult: PO CCr <50 mL/min, give 50% of dose
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