Is hydroxyzine (antihistamine) 10 mg effective for short-term anxiety relief?

Hydroxyzine 10 mg for Anxiety

Hydroxyzine 10 mg can provide short-term anxiety relief, though this dose is at the lower end of the effective range—the FDA-approved and guideline-supported dosing for anxiety typically starts at 25-50 mg daily, divided into multiple doses. 1

FDA-Approved Indication and Dosing

The FDA has approved hydroxyzine specifically for "symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested." 1 However, the FDA label emphasizes that the effectiveness of hydroxyzine as an antianxiety agent for long-term use (more than 4 months) has not been assessed by systematic clinical studies. 1

Evidence for Efficacy in Generalized Anxiety Disorder

Clinical trials demonstrate that hydroxyzine 50 mg daily is significantly more effective than placebo for generalized anxiety disorder (GAD), with anxiolytic effects beginning within the first week of treatment. 2, 3

• In a randomized, double-blind trial of 133 GAD patients, hydroxyzine 50 mg/day showed statistically significant reduction in anxiety scores compared to placebo by the end of week one, with sustained benefit throughout 4 weeks of treatment 2
• The anxiolytic effect persisted even one week after abrupt discontinuation, without rebound anxiety or withdrawal symptoms 2, 3
• A Cochrane systematic review (5 studies, 884 participants) confirmed hydroxyzine is more effective than placebo for GAD (OR 0.30,95% CI 0.15 to 0.58), though the review noted high risk of bias in included studies 4

Dosing Considerations for Anxiety

For anxiety management, the evidence supports 50 mg daily as the effective dose, which is substantially higher than the 10 mg dose in question. 2, 3

• The 10 mg dose falls within the range used for pediatric anxiolysis in medical procedures (10-25 mg) 5
• For adults with anxiety, clinical trials have not established efficacy at 10 mg as monotherapy 4, 2
• The 10 mg dose is more commonly used as an adjunctive nighttime dose for conditions like urticaria (10-50 mg at bedtime) rather than primary anxiety treatment 6, 7

Side Effect Profile

The most common side effect is transient drowsiness, occurring in approximately 28% of patients on hydroxyzine 50 mg versus 14% on placebo, typically appearing during the first week and progressively diminishing with continued treatment. 2

• Hydroxyzine causes sedation in approximately 80% of patients, higher than diphenhydramine (50%) or promethazine (60-73%) 6
• Other side effects include dry mouth (14% vs 5% placebo), weight gain (12% vs 10%), and loss of concentration (9% vs 8%) 2

Special Populations and Contraindications

Hydroxyzine should be avoided in early pregnancy, severe hepatic disease, and used with extreme caution in elderly patients due to high risk of sedation, falls, and cognitive impairment. 6, 7

• In moderate renal impairment (creatinine clearance 10-20 mL/min), reduce the dose by half 6, 7
• Elderly adults are at particularly high risk for anticholinergic side effects, especially with pre-existing prostatic hypertrophy, elevated intraocular pressure, or cognitive impairment 6
• Avoid concomitant use with other CNS depressants, as this enhances performance impairment and sedation 6

Clinical Bottom Line for 10 mg Dosing

While 10 mg hydroxyzine may provide mild anxiolytic effects through its sedating properties, this dose is below the evidence-based therapeutic range for treating anxiety disorders. 1, 2, 3 If prescribing for anxiety:

• Consider starting at 25 mg and titrating to 50 mg daily based on response and tolerability 2
• Limit use to short-term treatment (less than 4 months) as long-term efficacy is not established 1
• The 10 mg dose may be appropriate as an adjunctive nighttime agent for anxiety-related insomnia, but not as primary anxiolytic monotherapy 6, 7
• For GAD requiring longer-term management, SSRIs or cognitive behavioral therapy are preferred first-line treatments 5