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hydrOXYzine (Monograph)

Brand names: Anx, Atarax, Vistaril
Drug class: Anxiolytics, Sedatives, and Hypnotics; Miscellaneous
VA class: CN309
CAS number: 2192-20-3

Medically reviewed by Drugs.com on Jun 29, 2023. Written by ASHP.

Introduction

Antihistamine; piperazine-derivative.

Uses for hydrOXYzine

Anxiety

Symptomatic management of anxiety and tension associated with psychoneuroses and as an adjunct in patients with organic disease states who have associated anxiety; however, most clinicians consider other anxiolytic agents (e.g., benzodiazepines) more effective.

Has been used to allay anxiety in prepartum and postpartum states.

Has been used for prompt control of acutely disturbed or hysterical patients.

Pruritus

Management of pruritus caused by allergic conditions (e.g., chronic urticaria, atopic or contact dermatoses) and in histamine-mediated pruritus.

Preoperative and Postoperative Adjunctive Therapy

Sedation before and after general anesthesia.

Has been used to reduce opiate analgesic requirements.

Alcohol Withdrawal

Has been used to manage agitation caused by acute alcohol withdrawal.

Motion Sickness

Has been used to control motion sickness.

Nausea and Vomiting

Management of nausea and vomiting of various etiologies (e.g., postoperative).

Safety for prevention and treatment of nausea and vomiting of pregnancy not established; contraindicated during early pregnancy.

hydrOXYzine Dosage and Administration

Administration

Administer orally or by IM injection.

Do not administer parenteral preparation by sub-Q, intra-arterial, or IV injection.

Oral therapy should replace IM therapy as soon as possible.

IM Administration

For solution and drug compatibility information, see Compatibility under Stability.

Administer commercially available injection without further dilution.

Use caution to avoid extravasation or inadvertent sub-Q, IV, or intra-arterial injection (see Local Effects under Cautions). Z-track injection technique may prevent sub-Q infiltration.

Adults: Administer preferably deep into the upper outer quadrant of the gluteus maximus or the midlateral thigh. To avoid radial nerve injury, use the deltoid area with caution and only if well developed. Do not administer into the lower and mid-third of the upper arm.

Children: Administer into the midlateral muscles of the thigh.

Infants and small children: If IM injection is required, administer in the periphery of the upper outer quadrant of the gluteus maximus. (See Pediatric Use under Cautions.)

Dosage

Available as hydroxyzine pamoate and hydroxyzine hydrochloride; dosage expressed in terms of the hydrochloride.

Use the smallest possible effective dosage.

Pediatric Patients

Anxiety
Oral

Children <6 years of age: 50 mg daily given in divided doses.

Children ≥6 years of age: 50–100 mg daily given in divided doses.

Pruritus
Oral

Children <6 years of age: 50 mg daily given in divided doses.

Children ≥6 years of age: 50–100 mg daily given in divided doses.

Preoperative and Postoperative Adjunctive Therapy
Sedation
Oral

0.6 mg/kg administered before and following general anesthesia.

IM

1.1 mg/kg administered before and following general anesthesia.

Nausea and Vomiting
IM

Initially, 1.1 mg/kg; adjust subsequent dosage according to individual requirements and response.

Adults

Anxiety
Oral

50–100 mg 4 times daily.

Prepartum and Postpartum Anxiety
IM

Initially, 25–100 mg; adjust subsequent dosage according to individual requirements and response.

Acutely Disturbed or Hysterical Patients
IM

50–100 mg repeated every 4–6 hours as needed to control symptoms.

Pruritus
Oral

25 mg 3 or 4 times daily.

Preoperative and Postoperative Adjunctive Therapy
Sedation
Oral

50–100 mg administered before and following general anesthesia.

IM

25–100 mg administered before and following general anesthesia.

Reduction of Opiate Analgesic Requirements
IM

Initially, 25–100 mg; adjust subsequent dosage according to individual requirements and response.

Alcohol Withdrawal
IM

50–100 mg repeated every 4–6 hours as needed to control symptoms.

Nausea and Vomiting
IM

Initially, 25–100 mg; adjust subsequent dosage according to individual requirements and response.

Special Populations

Geriatric Patients

Use initial dosage at low end of the recommended dosage range. (See Geriatric Use under Cautions.)

Cautions for hydrOXYzine

Contraindications

Warnings/Precautions

General Precautions

Nervous System Effects

Possible drowsiness; performance of activities requiring mental alertness or physical coordination may be impaired.

Concurrent use of other CNS depressants may potentiate CNS depression. (See Specific Drugs under Interactions.)

Local Effects

Possible marked local discomfort, sterile abcesses, erythema, local irritation, and tissue necrosis at injection site; extravasation may cause marked localized sub-Q tissue induration. (See Administration under Dosage and Administration.)

Phlebitis and hemolysis reported following IV administration.

Specific Populations

Pregnancy

Category C. Contraindicated in early pregnancy.

Lactation

Not known whether hydroxyzine is distributed into milk. Use is not recommended.

Pediatric Use

Possible damage to sciatic nerve associated with IM administration in infants and small children; administer IM only when necessary in the periphery of the upper outer quadrant of the gluteus maximus.

Geriatric Use

Response similar to that in younger adults, however, possible increased risk of sedative effects. Close observation and cautious dosing recommended.

Common Adverse Effects

Drowsiness, dry mouth.

Drug Interactions

Specific Drugs

Drug

Interaction

Comments

Anticholinergic agents

Additive anticholinergic effects

CNS depressants (e.g., alcohol, opiates and other analgesics, anesthetics, barbiturates, sedatives)

Additive CNS effects

Use caution to avoid excessive sedation; reduce CNS depressant dosage by up to 50%

Epinephrine

Inhibition and reversal of vasopressor effect of epinephrine

If vasopressor is required, use alternative drug (e.g., norepinephrine)

hydrOXYzine Pharmacokinetics

Absorption

Bioavailability

Rapidly absorbed following oral administration.

Onset

Onset of sedative action is 15–30 minutes following oral administration.

Duration

Sedative effect persists for 4–6 hours following single dose.

Suppresses the inflammatory response (wheal and flare reaction) and pruritus for up to 4 days after intradermal skin tests with allergens and histamine.

Distribution

Extent

Widely distributed into most body tissues and fluids in animals. Not known whether hydroxyzine crosses the placenta or is distributed into milk.

Elimination

Metabolism

Exact metabolic fate not clearly established; appears to be completely metabolized, principally in the liver. Carboxylic acid metabolite is cetirizine, a long-acting antihistamine.

Elimination Route

Excreted in feces via biliary elimination.

Half-life

20 hours.

Stability

Storage

Oral

Capsules

Tight, light-resistant containers at ≤40°C (preferably 15–30°C).

Suspension or Solution

Tight, light-resistant containers at ≤40°C (preferably 15–30°C). Avoid freezing.

Parenteral

Injection

<30°C. Avoid freezing.

Compatibility

Parenteral

Drug Compatibility
Syringe CompatibilityHID

Compatible

Atropine sulfate

Buprenorphine HCl

Butorphanol tartrate

Chlorpromazine HCl

Diphenhydramine HCl

Doxapram HCl

Droperidol

Fentanyl citrate

Fluphenazine HCl

Glycopyrrolate

Hydromorphone HCl

Lidocaine HCl

Meperidine HCl

Metoclopramide HCl

Midazolam HCl

Morphine sulfate

Nalbuphine HCl

Pentazocine lactate

Prochlorperazine edisylate

Promethazine HCl

Scopolamine HBr

Incompatible

Dimenhydrinate

Haloperidol lactate

Ketorolac tromethamine

Pentobarbital sodium

Ranitidine HCl

Actions

Advice to Patients

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

hydrOXYzine Hydrochloride

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Solution

10 mg/5 mL*

Atarax Syrup

Pfizer

Tablets

10 mg*

Atarax

Pfizer

25 mg*

Atarax

Pfizer

50 mg*

Atarax

Pfizer

100 mg

Atarax

Pfizer

Tablets, film-coated

25 mg*

Anx (scored)

EconoMed

Parenteral

Injection, for IM use only

25 mg/mL*

Vistaril

Pfizer

50 mg/mL*

Vistaril

Pfizer

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

hydrOXYzine Pamoate

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Oral

Capsules

equivalent to hydroxyzine hydrochloride 25 mg*

Vistaril

Pfizer

equivalent to hydroxyzine hydrochloride 50 mg*

Vistaril

Pfizer

equivalent to hydroxyzine hydrochloride 100 mg*

Vistaril

Pfizer

Suspension

equivalent to hydroxyzine hydrochloride 25 mg/5 mL

Vistaril

Pfizer

AHFS DI Essentials™. © Copyright 2024, Selected Revisions July 9, 2013. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

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