Hydroxyzine Side Effects

Medically reviewed by Drugs.com. Last updated on Jan 2, 2025.

Applies to hydroxyzine: intramuscular solution.

Other dosage forms:

• oral capsule, oral syrup, oral tablet

Common side effects of hydroxyzine

Some side effects of hydroxyzine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Rare side effects

• shakiness in the legs, arms, hands, or feet
• trembling or shaking of the hands or feet

Incidence not known

• drowsiness
• dry mouth

Serious side effects of hydroxyzine

Along with its needed effects, hydroxyzine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking hydroxyzine:

Incidence not known

• bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
• blue-green to black skin discoloration
• pain, redness, or sloughing of skin at the injection site

For healthcare professionals

Applies to hydroxyzine: compounding powder, intramuscular solution, oral capsule, oral suspension, oral syrup, oral tablet.

General adverse events

The most commonly reported side effects included sleepiness, headache, and tiredness.^[Ref]

Nervous system

• Very common (10% or more): Sleepiness (up to 13.74%)
• Common (1% to 10%): Headache
• Rare (0.01% to 0.1%): Convulsion, tremor
• Frequency not reported: Anticholinergic activity, central nervous system (CNS) depression, drowsiness, incoordination, involuntary motor activity, psychomotor impairment, stimulation
• Postmarketing reports: Dizziness, dyskinesia, dystonia, paresthesia, sedation, seizures, syncope^[Ref]

Other

• Common (1% to 10%): Tiredness
• Frequency not reported: Antimuscarinic effects, lassitude
• Postmarketing reports: Asthenia, malaise, pyrexia, sudden death^[Ref]

Gastrointestinal

• Common (1% to 10%): Dry mouth
• Postmarketing reports: Constipation, diarrhea, nausea, vomiting^[Ref]

Cardiovascular

• Frequency not reported: QT prolongation, Torsade de Pointes
• Postmarketing reports: Cardiac arrest, cardiac arrhythmias, edema, hypotension, ventricular arrhythmias, ventricular fibrillation, ventricular tachycardia^[Ref]

Hypersensitivity

• Frequency not reported: Hypersensitivity reaction
• Postmarketing reports: Allergic reaction, anaphylactic shock, angioedema, hypersensitivity^[Ref]

Respiratory

• Frequency not reported: Respiratory depression
• Postmarketing reports: Bronchospasm^[Ref]

Dermatologic

• Postmarketing reports: Acute generalized exanthematous pustulosis (AGEP), bullous condition (pemphigoids, toxic epidermal necrolysis), dermatitis, erythema, erythema multiforme, fixed drug eruptions, increased sweating, maculopapular rash, pruritus, rash, Stevens-Johnson syndrome, urticaria^[Ref]

Psychiatric

• Postmarketing reports: Aggression, agitation, confusion, depression, disorientation, hallucination, insomnia, tics^[Ref]

Genitourinary

• Postmarketing reports: Dysuria, enuresis, urinary retention^[Ref]

Ocular

• Postmarketing reports: Accommodation disorder, blurred vision, oculogyric crisis^[Ref]

Hepatic

• Postmarketing reports: Hepatitis, liver function tests abnormal^[Ref]

Hematologic

• Postmarketing reports: Thrombocytopenia^[Ref]

Metabolic

• Postmarketing reports: Weight gain^[Ref]

Frequently asked questions

• Can you take hydroxyzine for anxiety and sleep?
• Can hydroxyzine be taken long-term?
• Does Benadryl help with or cause anxiety?
• When can I start drinking if I’m no longer taking hydroxyzine?
• Can dogs take hydroxyzine?
• Can you take antihistamines when pregnant?

Further information

Hydroxyzine side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer