Key uses of hydroxyzine hydrochloride tablet
Hydroxyzine hydrochloride, available under brand names like Atarax®, is a prescription-only medication approved for several therapeutic uses. As a first-generation antihistamine, it provides symptomatic relief for various conditions by blocking the action of histamine and suppressing activity in the central nervous system.
Relieving anxiety and tension
One of the primary uses of hydroxyzine hydrochloride is for the management of anxiety and tension, particularly associated with psychoneuroses and emotional stress. It is important to note that while effective for short-term relief, its long-term efficacy (beyond 4 months) has not been definitively established and its use should be periodically reassessed by a healthcare provider.
Treating allergic itching (pruritus)
Hydroxyzine is commonly prescribed to alleviate itching caused by various allergic skin reactions, such as chronic urticaria (hives), atopic dermatitis (eczema), and contact dermatitis. Its antihistamine properties help to control the symptoms by blocking histamine, a substance that triggers allergic responses.
Promoting sedation
The sedative properties of hydroxyzine are often leveraged to help patients feel relaxed or sleepy in specific situations.
- Before and after surgery: It is used as a sedative and to control anxiety in patients undergoing general anesthesia for surgery.
- For sleep issues: While not FDA-approved specifically for insomnia, it is sometimes used off-label for short-term sleep difficulties due to its sedating effects.
Treating nausea and vomiting
Hydroxyzine can be used to control nausea and vomiting, excluding those related to pregnancy. Its antiemetic effects are thought to be related to its central anticholinergic and CNS depressant properties.
The pharmacology of hydroxyzine hydrochloride
Hydroxyzine is a first-generation antihistamine that primarily works as a potent inverse agonist of the histamine H1 receptor. This action blocks the effects of histamine, which is responsible for triggering many allergy symptoms. The drug also has additional properties that contribute to its wider range of uses:
- Central Nervous System (CNS) Depression: The sedative and tranquilizing effects are believed to result from the suppression of activity in subcortical areas of the brain.
- Anticholinergic effects: These properties contribute to its antiemetic and anti-motion sickness actions, though they can also lead to side effects like dry mouth and blurred vision.
- Serotonergic activity: Some research suggests hydroxyzine can increase serotonin levels in the brain, contributing to mood stabilization and anxiolytic effects.
Comparison: Hydroxyzine vs. Diphenhydramine
Hydroxyzine (Atarax) is often compared with other first-generation antihistamines like diphenhydramine (Benadryl). While both cause sedation, there are notable differences.
| Feature | Hydroxyzine (Atarax) | Diphenhydramine (Benadryl) |
|---|---|---|
| Availability | Prescription only | Available over-the-counter |
| Uses | Approved for anxiety, itching, and sedation | Approved for allergies, cold symptoms, and itching; often used as a sleep aid |
| Mechanism | Blocks H1 receptors; affects serotonin and provides anxiolytic effects | Blocks H1 receptors; primarily used for allergic reactions |
| Onset | Works within 15-30 minutes | Works within 15-30 minutes |
| Duration of action | Lasts longer in the system (up to 5 days) | Shorter duration, taken every 4-6 hours |
| Side effects | Drowsiness, dry mouth, headache, confusion. Can cause heart rhythm issues (long QT). | Significant drowsiness, dry mouth. |
| Special precautions | Avoid in early pregnancy, use caution with heart conditions (long QT), or in elderly. | Not recommended for long-term use; be aware of overuse in OTC products. |
Important precautions and side effects
Like all medications, hydroxyzine hydrochloride comes with important considerations and potential side effects.
- Sedation and drowsiness: This is a common side effect and can impair mental alertness and physical coordination. Patients should avoid driving or operating heavy machinery until they know how the medication affects them.
- Heart rhythm problems: Hydroxyzine carries a risk of QT prolongation, a condition that affects heart rhythm. It is contraindicated in patients with a prolonged QT interval and should be used with caution in those with a family history of heart rhythm issues.
- Anticholinergic side effects: These include dry mouth, blurred vision, urinary retention, and constipation.
- Drug interactions: Hydroxyzine can interact with other CNS depressants, such as alcohol, opioids, and benzodiazepines, which can increase sedation. It should also be used with caution alongside other medications that prolong the QT interval, including certain antibiotics and antidepressants.
- Use in specific populations: It is not recommended during early pregnancy. In elderly patients, lower doses are often prescribed due to increased sensitivity to side effects like confusion and sedation.
Conclusion
Hydroxyzine hydrochloride tablets are a versatile and effective prescription medication for the short-term relief of allergic itching, anxiety, and as a sedative before and after surgery. Its mechanism involves blocking histamine, which is responsible for allergic symptoms, and acting as a CNS depressant. While it offers significant benefits, particularly as a non-habit-forming option for anxiety, it is crucial to be aware of potential side effects, including drowsiness and a risk of heart rhythm abnormalities. It is important for patients to discuss their full medical history and all other medications with their doctor to ensure safe and effective use. For comprehensive information, consult resources like the official MedlinePlus drug information page.
