Hydroxyzine: what it treats, how to take it, side effects
Last updated September 3, 2026.
Hydroxyzine is an antihistamine used for itching from allergic skin reactions, for anxiety and tension, and as a sedative around surgery. You may know it as Vistaril or Atarax. It blocks histamine and also decreases activity in the brain, which is where the drowsiness comes from.
What does it treat?
Three jobs, per MedlinePlus and the label: relieving itching from allergic skin conditions like chronic hives and dermatitis, relieving anxiety and tension, and providing sedation before and after general anesthesia for surgery. The label notes its effectiveness for anxiety beyond 4 months has not been systematically studied, so longer-term use should be reassessed periodically by your doctor.
How do you take it?
By mouth as a capsule, tablet, or syrup, usually three or four times a day as your doctor directs. Label dosing for adults: for anxiety and tension, 50 to 100 mg four times a day; for itching, 25 mg three or four times a day; as a sedative, 50 to 100 mg. Exact doses vary by person - the label says dosing is adjusted to your response. If you miss a dose on a regular schedule, take it when you remember unless the next one is close; never double up.
Side effects to know
- Common: dry mouth, dizziness, headache, and confusion, especially in older adults. Drowsiness is expected - it is part of how the drug works.
- Serious: unintentional trembling or shaking movements; seizures; and a severe skin reaction with rash, pus-filled blister-like sores, swelling and redness, and fever. Call your doctor immediately for any of these.
Who should not take it?
If you have a prolonged QT interval, your doctor will probably tell you not to take hydroxyzine - and mention any family history of it, or personal history of slow or irregular heartbeat, heart failure, or heart attack. You should not take hydroxyzine while pregnant (call your doctor immediately if you become pregnant) and you should not breastfeed while taking it. Adults 65 and older should usually avoid it because it is not as safe as other options for the same conditions. The label warns it amplifies other central nervous system depressants - narcotics, non-narcotic painkillers, barbiturates - so their doses need adjusting when combined. No driving until you know how it affects you, and alcohol makes its side effects worse.
When is it an emergency?
Call 911 for seizures, for fainting or an irregular heartbeat, and for the severe skin reaction with fever and blistering sores. Overdose mainly shows as extreme sedation, and can include convulsions, stupor, nausea, and vomiting - call Poison Control at 1-800-222-1222, or 911 if the person cannot be awakened. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
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Common questions
Does hydroxyzine make you sleepy?
Yes - sedation is built into how it works, and MedlinePlus lists drowsiness prominently enough to warn against driving or operating machinery until you know how it affects you. Many people schedule doses around this effect, especially the last one at bedtime.
Can I drink alcohol while taking hydroxyzine?
Ask your doctor, because MedlinePlus says alcohol can make hydroxyzine's side effects worse. The label also warns that hydroxyzine amplifies other central nervous system depressants - and alcohol is one. Combining them raises the risk of dangerous over-sedation.
Is hydroxyzine a benzodiazepine?
No. It is an antihistamine with calming and sedating effects, which is why doctors use it for short-term anxiety relief in people they want to keep off habit-forming medications. The trade-off: the label notes its effectiveness for anxiety beyond 4 months has not been systematically studied, so it is not a set-and-forget medication.
Why did my doctor ask about my heart before prescribing it?
Because of heart rhythm. MedlinePlus says people with a prolonged QT interval will probably be told not to take hydroxyzine, and it asks about family history of that condition and about heart failure, heart attack, and slow or irregular heartbeat. The questions are the safety screen working as intended.
Can older adults take hydroxyzine?
Usually they should not. MedlinePlus says adults 65 and older should generally avoid hydroxyzine because it is not as safe as other medications for the same conditions - confusion and over-sedation are particular risks. The label adds that elderly patients should start on low doses and be observed closely when it is used.
Can I take hydroxyzine while pregnant?
No. MedlinePlus is direct: you should not take hydroxyzine if you are pregnant, and if you become pregnant while taking it, call your doctor immediately. You should also not breastfeed while taking it.