Hyzine Side Effects
Generic name: hydroxyzine
Medically reviewed by Drugs.com. Last updated on Jun 17, 2022.
Note: This document contains side effect information about hydroxyzine. Some of the dosage forms listed on this page may not apply to the brand name Hyzine.
For the Consumer
Applies to hydroxyzine: intramuscular solution
Side effects requiring immediate medical attention
Along with its needed effects, hydroxyzine (the active ingredient contained in Hyzine) 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
Side effects not requiring immediate medical attention
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:
- Shakiness in the legs, arms, hands, or feet
- trembling or shaking of the hands or feet
Incidence not known
- dry mouth
For Healthcare Professionals
Applies to hydroxyzine: compounding powder, intramuscular solution, oral capsule, oral suspension, oral syrup, oral tablet
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
Common (1% to 10%): Tiredness
Frequency not reported: Antimuscarinic effects, lassitude
Postmarketing reports: Asthenia, malaise, pyrexia, sudden death[Ref]
Common (1% to 10%): Dry mouth
Frequency not reported: QT prolongation, Torsade de Pointes
Frequency not reported: Hypersensitivity reaction
Frequency not reported: Respiratory depression
Postmarketing reports: Bronchospasm[Ref]
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]
Postmarketing reports: Accommodation disorder, blurred vision, oculogyric crisis[Ref]
Postmarketing reports: Weight gain[Ref]
Frequently asked questions
- Can hydroxyzine be taken long-term?
- Can you take antihistamines when pregnant?
- When can I start drinking if I’m no longer taking hydroxyzine?
More about Hyzine (hydroxyzine)
- Drug interactions
- Dosage information
- During pregnancy or Breastfeeding
- Reviews (3)
- Drug class: antihistamines
Related treatment guides
1. "Product Information. Vistaril (hydroxyzine)." Pfizer U.S. Pharmaceuticals (2001):
2. "Product Information. Atarax (hydroxyzine)." Pfizer U.S. Pharmaceuticals (2001):
3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Some side effects may not be reported. You may report them to the FDA.