Contraindications for Hydroxyzine
Hydroxyzine is absolutely contraindicated in patients with known hypersensitivity to hydroxyzine, cetirizine, or levocetirizine; prolonged QT interval; and early pregnancy. 1
Absolute Contraindications
The FDA label clearly defines the following as absolute contraindications 1:
- Known hypersensitivity to hydroxyzine hydrochloride products 1
- Cross-sensitivity to cetirizine hydrochloride or levocetirizine hydrochloride 1
- Prolonged QT interval on baseline ECG 1
- Early pregnancy - hydroxyzine induced fetal abnormalities in animal studies at doses above human therapeutic range, and clinical data in humans are inadequate to establish safety 1
Conditions Requiring Avoidance
Based on guideline recommendations, hydroxyzine should be avoided in 2, 3:
- Severe renal impairment (creatinine clearance <10 mL/min) 2
- Severe liver disease due to enhanced sedating effects 2, 3
High-Risk Situations Requiring Extreme Caution
While not absolute contraindications, the following warrant serious consideration before prescribing 1:
Cardiac Risk Factors
- Pre-existing heart disease - cases of QT prolongation and Torsade de Pointes reported in post-marketing surveillance 1
- Congenital long QT syndrome or family history of long QT syndrome 1
- Recent myocardial infarction 1
- Uncompensated heart failure 1
- Bradyarrhythmias 1
- Electrolyte imbalances predisposing to arrhythmias 1
Drug Interactions
- Concomitant QT-prolonging medications including Class 1A antiarrhythmics (quinidine, procainamide), Class III antiarrhythmics (amiodarone, sotalol), certain antipsychotics (ziprasidone, quetiapine, chlorpromazine), antidepressants (citalopram, fluoxetine), antibiotics (azithromycin, erythromycin, moxifloxacin), and others (methadone, ondansetron) 1
- CNS depressants (narcotics, barbiturates, alcohol) - hydroxyzine potentiates their effects and dosages must be reduced 1
Special Populations
- Elderly patients - increased risk of confusion, oversedation, and falls; start with low doses 1
- Moderate renal impairment - dose must be halved 2, 3
Clinical Pearls for Evening Anxiety Use
For your specific use case of evening anxiety 3:
- Typical dosing is 10-50 mg at bedtime 3
- Hydroxyzine works well as a nighttime adjunct to non-sedating medications used during the day 3, 4
- Avoid prolonged monotherapy due to concerns about reduced concentration and performance 3
- Patients must be warned about driving impairment and advised against alcohol use 1
- Consider lower starting doses (10-25 mg) in elderly or frail patients 3
Common Pitfall to Avoid
The most critical error is prescribing hydroxyzine without screening for QT prolongation risk factors and concomitant QT-prolonging medications 1. Always review the patient's medication list and consider baseline ECG in high-risk patients before initiating therapy 1.