Atarax (Hydroxyzine) Overview

Generic Name

Hydroxyzine

Brand Names

Vistaril, Atarax

Drug Class

Antihistamine

Mechanism of Action

Hydroxyzine primarily acts by inhibiting the H1 receptors in the body, which blocks the effect of histamine, a substance in the body that causes allergic symptoms. Additionally, it has sedative properties due to its effect on the central nervous system.

Indications

Hydroxyzine is commonly prescribed for the management of anxiety and tension associated with psychoneurosis. It is also used as a sedative premedication and to treat pruritus due to allergic conditions.

Dosage Information

Administration Route

Oral, Intramuscular

Standard Dosage

Adults may be prescribed 25 to 100 milligrams daily, depending on the severity and indication. In children, the dosage is usually adjusted based on body weight and the specific condition being treated.

Dosage Adjustments

Dosages may need to be lowered for elderly patients or those with impaired hepatic or renal function. Physicians will typically adjust dosages in increments to minimize potential side effects.

Pharmacokinetics

Absorption

Hydroxyzine is rapidly absorbed from the gastrointestinal tract.

Metabolism

The liver metabolizes hydroxyzine to cetirizine, a less potent H1 antagonist.

Half-life

The elimination half-life of hydroxyzine is approximately 20 to 25 hours in healthy adults.

Excretion

Metabolites are primarily excreted in the urine. A smaller amount may be excreted via feces.

Possible Side Effects

Common Side Effects

Common adverse reactions may include drowsiness, dry mouth, dizziness, and headache.

Serious Side Effects

Rare but serious side effects can include confusion, hallucinations, and seizures.

Allergic Reactions

Hydroxyzine can cause allergic reactions including anaphylaxis, which requires immediate medical attention.

Drug Interactions

Hydroxyzine may interact with other central nervous system depressants, including alcohol and certain other drugs, leading to increased sedation or respiratory depression.

Special Populations

Pregnancy Category

Hydroxyzine is classified as Pregnancy Category C. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breastfeeding

Due to the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or discontinue the drug, considering the importance of the drug to the mother.

Pediatric Use

The safety and efficacy of hydroxyzine in children under the age of 6 months have not been established.

Geriatric Use

In elderly patients, dosages should start at the lower end of the dosing range. Special attention should be given to the increased risk of side effects such as sedation and confusion.

Laboratory Monitoring

Liver Function

Patients on long-term hydroxyzine therapy should undergo periodic liver function tests.

Renal Function

Monitoring of renal function is recommended because of the drug’s excretion pathway and the increased risk of accumulation in renal impairment.

Storage and Handling

Storage Conditions

Store hydroxyzine at room temperature, away from light and moisture. Do not store in the bathroom. Keep out of reach of children and pets.

Handling Precautions

Healthcare providers should handle hydroxyzine according to standard safety protocols to prevent accidental ingestion or contact.

Disposal Guidelines

Unused Medication

Any unused or expired hydroxyzine should be disposed of in accordance with local regulations. Do not flush medications down the toilet unless instructed to do so.

Pharmacy Disposal

Pharmacies often offer take-back programs for the safe disposal of medications. Check with your local pharmacy for available options.