What is Atarax? Uses, Side Effects, and Pharmacology Explained

October 7, 2025 •

2 min read

According to a 2023 report, hydroxyzine (the active ingredient in Atarax) was one of the most commonly prescribed medications in the United States, with over 15 million prescriptions. Understanding what is Atarax and how it works is crucial for those managing anxiety, allergies, and other conditions it treats.

Quick Summary

Atarax (hydroxyzine) is a prescription-only first-generation antihistamine. It is used to relieve symptoms of anxiety, itching from allergic skin conditions like chronic urticaria, and as a sedative before and after anesthesia. It works by blocking histamine receptors in the body and brain.

Key Points

Antihistamine with sedating properties: Atarax (hydroxyzine) is a first-generation antihistamine that is more sedating than modern options because it crosses the blood-brain barrier.
Used for multiple conditions: It is primarily prescribed for short-term anxiety relief, severe allergic itching (hives), and as a sedative before and after surgery.
Risk of drowsiness and impairment: Due to its potent sedative effects, Atarax can cause significant drowsiness and should be used with caution, especially when driving or operating heavy machinery.
Important drug interactions: Atarax's effects are amplified by alcohol and other central nervous system depressants. It can also increase the risk of irregular heart rhythms when combined with certain other medications.
Available in various forms: It comes in tablets and oral solutions (syrup), as well as capsules, with administration frequency varying depending on the condition being treated.
Short-term use is recommended: The effectiveness of Atarax for long-term anxiety treatment is not established, and its use is typically limited for this purpose.

Understanding Atarax (Hydroxyzine)

Atarax is the brand name for the generic drug hydroxyzine hydrochloride, a first-generation antihistamine. It can cross the blood-brain barrier, allowing it to act on the central nervous system (CNS) and produce sedative and anti-anxiety effects. It has been used since 1956 for multiple purposes.

Mechanism of action

Atarax primarily blocks histamine H1 receptors, counteracting the effects of histamine which causes allergic symptoms. In the CNS, it also has effects on serotonin receptors and acetylcholine, contributing to its anxiolytic and sedative properties.

Approved medical uses

Atarax is FDA-approved for several uses:

Relief of anxiety and tension: Used for short-term anxiety, often while other treatments begin. Not recommended for long-term use.
Management of allergic skin conditions: Effective for itching (pruritus) from conditions like hives, eczema, and contact dermatitis.
Sedation: Used to help patients relax before and after surgery.
Nausea: Can help manage nausea and vomiting.

Dosage forms and administration

Atarax (hydroxyzine hydrochloride) is available as tablets and an oral solution. Capsules (typically Vistaril, hydroxyzine pamoate) are also available. The frequency of administration depends on the condition being treated and the form of the medication. Effects typically begin within 15-30 minutes and can last for several hours.

Important considerations when taking Atarax

Side effects

Atarax is known for its sedative properties.

Common side effects include:

Drowsiness
Dry mouth, headache, dizziness
Constipation
Blurred vision

Less common but serious side effects can occur:

QT prolongation: A rare irregular heart rhythm risk, higher in older adults or with certain other drugs.
Excessive sedation or confusion: More likely in older adults.
Severe skin reactions: Rare blistering rashes.

Drug interactions

Atarax can interact with other medications, increasing side effect risk.

CNS Depressants: Increased sedation with alcohol, opioids, benzodiazepines, and other sedatives.
Anticholinergic Drugs: Increased side effects like dry mouth and constipation when combined with other anticholinergic medications.
QT-Prolonging Drugs: Increased risk of heart rhythm problems with certain antipsychotics, antidepressants, and antibiotics.
Grapefruit Juice: May increase hydroxyzine levels and side effect risk.

Atarax vs. Second-Generation Antihistamines

Compared to newer antihistamines like cetirizine (Zyrtec), Atarax has significant differences.


Feature	Atarax (Hydroxycine)	Zyrtec (Cetirizine)
Generation	First-generation	Second-generation
CNS Effects	Causes significant drowsiness and anxiolytic effects	Causes much less drowsiness
Primary Use	Anxiety, sedation, severe allergic itching	General allergy symptoms
Availability	Prescription-only	Over-the-counter
Potential Risks	Higher risk of severe sedation, QT prolongation, confusion	Generally safer with lower risk of severe side effects

Conclusion

What is Atarax? It is a first-generation antihistamine with sedative and anti-anxiety properties used for short-term anxiety, allergic itching, and sedation. Due to potential side effects like drowsiness and interactions, especially with other CNS depressants and cardiac medications, careful prescription and patient education are vital. Its CNS impact means it requires caution, particularly in older adults, and is not for long-term treatment. Discussing the benefits and risks with a healthcare provider is essential for safe and effective use.

Learn More About Hydroxyzine

For more in-depth drug information, visit the MedlinePlus drug information page on Hydroxyzine.

Frequently Asked Questions

Atarax is an antihistamine, while Xanax is a benzodiazepine. While both can treat anxiety, they work differently. Atarax is not a controlled substance and is considered non-habit-forming, whereas Xanax has a high potential for dependence.

Atarax typically starts working within 15 to 30 minutes, with full effect taking up to two hours. Its effects can last for several hours.

Common side effects include drowsiness, dry mouth, dizziness, and headache. These are usually mild and may decrease over time.

No, avoid alcohol with Atarax as it significantly increases sedative effects, leading to excessive drowsiness and impaired function.

Use Atarax cautiously in older adults due to increased risk of confusion, excessive sedation, and cardiovascular issues. Administration for older adults requires careful consideration.

While not highly addictive, stopping Atarax suddenly can cause rebound symptoms like increased anxiety, insomnia, or itching. Discontinuation should be managed under a doctor's supervision.

The difference is the salt form of hydroxyzine. Atarax (hydrochloride) is usually tablets or syrup, while Vistaril (pamoate) is in capsules. Both are used for similar conditions.