Can hydroxyzine (an antihistamine) cause irritability?

Hydroxyzine Can Cause Irritability

Yes, hydroxyzine can cause irritability as a documented side effect. 1 According to pediatric guidelines, hydroxyzine has been specifically associated with irritability, along with tremors, hyperactivity, jitteriness, shrill cry, and other neurological symptoms.

Evidence for Hydroxyzine-Induced Irritability

Hydroxyzine, a first-generation antihistamine, has several documented neurological and behavioral side effects:

• The American Academy of Pediatrics specifically lists irritability as a recognized adverse effect of hydroxyzine 1
• This irritability may occur alongside other neurological symptoms including:
  • Tremors
  • Hyperactivity
  • Jitteriness
  • Shrill crying
  • Myoclonic jerks
  • Feeding problems

Mechanism and Risk Factors

The irritability caused by hydroxyzine is likely related to its effects on the central nervous system:

• As a first-generation antihistamine, hydroxyzine crosses the blood-brain barrier more readily than second-generation antihistamines 1
• It has significant CNS effects that can manifest as both sedation and paradoxical stimulation 1
• Paradoxical CNS stimulation may occur particularly in children, which could present as irritability 1

Patient Considerations

Certain populations may be at higher risk for experiencing irritability with hydroxyzine:

• Children appear particularly susceptible to paradoxical reactions 1
• Elderly patients should be started at the lowest possible dose (10 mg) due to increased sensitivity to CNS effects 2
• Patients with renal impairment may experience enhanced side effects due to altered drug clearance 1, 2

Management Recommendations

If irritability occurs with hydroxyzine use:

1. Consider discontinuing hydroxyzine and switching to a second-generation antihistamine
2. Second-generation antihistamines are generally preferred over first-generation antihistamines like hydroxyzine for allergic conditions 1
3. If hydroxyzine must be continued, consider:
   • Reducing the dose
   • Changing to evening-only dosing to minimize daytime side effects 3
   • Monitoring for worsening symptoms

Other Important Considerations

• Hydroxyzine can cause performance impairment without subjective awareness of drowsiness 4
• Evening dosing of hydroxyzine may help mitigate some adverse effects while maintaining efficacy 3
• Concomitant use with other CNS-active substances (alcohol, sedatives, antidepressants) may enhance adverse effects 1, 2
• Irritability has been reported to persist for up to 5 weeks after discontinuation in some cases 1

Common Pitfalls

1. Failing to recognize irritability as a hydroxyzine side effect rather than a symptom of the underlying condition
2. Continuing hydroxyzine despite irritability when second-generation alternatives are available
3. Not considering drug interactions that may exacerbate irritability
4. Overlooking that hydroxyzine's effects may persist for weeks after discontinuation in some cases 1

In conclusion, irritability is a recognized side effect of hydroxyzine that should prompt consideration of alternative treatments, particularly second-generation antihistamines that have less CNS penetration and fewer behavioral side effects.