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Hydroxyzine (Atarax)

Hydroxyzine is an antihistamine with anticholinergic and sedative properties used to treat allergic reactions, anxiety, and tension.

Last Modified: 22 May 2024

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What is Hydroxyzine? 

Hydroxyzine is an antihistamine with anticholinergic and sedative properties used to treat allergic reactions, anxiety, and tension. It contains hydroxyzine hydrochloride or hydroxyzine pamoate as the active ingredients. 

Chemically, hydroxyzine is synthesized through a series of organic reactions, resulting in a compound that blocks histamine H1-receptors. 

Global Name

Generic Name and Brand Names 

  • Generic name: Hydroxyzine
  • Brand names: Atarax (as the HCl form), Iterax, Vistaril (as the pamoate form), 


What is Hydroxyzine used for?

Hydroxyzine is used to: 

  • Relieve itching caused by allergies. 
  • Manage anxiety and tension due to psychological and emotional conditions. 
  • In combination with other medications for anesthesia. 
  • Control nausea and vomiting. 
  • As part of the treatment of alcohol withdrawal symptoms. 

How do you use Hydroxyzine?


Hydroxyzine is available in tablet, syrup, and injectable forms. 

Dosage information: 

  • For anxiety and tension (as Hydroxyzine pamoate): 50 to 100 mg four times a day. 
  • For allergies (as Hydroxyzine HCl): 25 mg three to four times a day. 

Suitable for: 

  • Children: Yes, but dosage will differ based on the condition and age. 
  • Adults: Yes 
  • Elderlies: Yes, but may require a lower dose. 

Who can't take Hydroxyzine? 

  • Children: Caution in young children and infants. 
  • Adults: Those with a history of hypersensitivity to hydroxyzine. 
  • Elderlies: May be more sensitive to side effects. 
  • Pregnancy: Can cause fetal abnormalities when used in early pregnancy (based on animal studies; US FDA Category C). Use only if advised by healthcare professionals weighing the risks versus benefits. 
  • Lactation: Not recommended as it can pass into breast milk. 

Allergies: Not suitable for individuals with a known allergy to hydroxyzine or cetirizine. 

Warnings and precautions: Use with caution in patients with a history of heart problems, urinary retention, glaucoma, or thyroid disorders. It may cause drowsiness, so avoid driving or operating machinery. 

Hydroxyzine can be taken with or without food but should be taken with a full glass of water. 

Interactions and contraindications: Avoid alcohol as it can enhance drowsiness. Hydroxyzine may interact with certain medications, such as other CNS depressants and anticholinergic drugs. 

Side Effects

Common side effects include drowsiness, dry mouth, and headache. Serious side effects may involve irregular heartbeat and seizures. 

Pharmacist Tips

  • Drowsiness: Hydroxyzine can cause drowsiness; avoid activities requiring mental alertness until you know how it affects you. 
  • Dry Mouth: Sucking on sugarless candy or ice chips can help alleviate dry mouth caused by hydroxyzine. 
  • Storage: Store at room temperature, protect from light and moisture, and keep out of reach of children and pets. 
  • Handling: If you are taking the liquid form, measure doses carefully with a proper measuring device/spoon. 


Where is Hydroxyzine available in Hong Kong?

Hydroxyzine is a prescription medication that can be prescribed by healthcare providers.


Is Hydroxyzine available over-the-counter?

No, Hydroxyzine requires a prescription from a healthcare provider.

Can Hydroxyzine be used for long-term anxiety treatment?

Hydroxyzine pamoate is typically used for short-term relief of anxiety symptoms. Long-term treatment should be discussed with a healthcare provider.

What should you do if you experience severe side effects from Hydroxyzine?

Seek immediate medical attention if you experience severe side effects such as difficulty breathing, swelling of the face, or irregular heartbeat. If possible, bring the medication to the consultation for easier identification.

How long does Hydroxyzine last for sleep?  

Hydroxyzine's sedative effects typically last for around 4 to 6 hours, but the drug can remain in the system for up to 24 hours. Always use it as directed by a healthcare provider, as individual responses can vary. 


This website provides content related to drug use and medicine for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Do not use the information on this website to diagnose or treat a health problem or disease without consulting a qualified healthcare provider. The website's owners and contributors are not liable for any repercussions, adverse effects, or consequences resulting from the use of any medication or information provided herein.

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