Atarax (Hydroxyzine) Dosing in ESRD
Reduce the hydroxyzine dose and start at the low end of the dosing range in patients with end-stage renal disease, as the extent of renal excretion is undetermined and elderly ESRD patients are at higher risk for sedation and confusion. 1
Primary Dosing Recommendation
The FDA label specifically states that because the extent of renal excretion of hydroxyzine has not been determined, and because elderly patients (who comprise a significant proportion of ESRD patients) are more likely to have decreased renal function, care should be taken in dose selection, with elderly patients generally started on low doses and observed closely. 1
Rationale for Dose Reduction
- Sedating drugs like hydroxyzine may cause confusion and over-sedation in elderly patients, who should be started on low doses and monitored carefully 1
- The FDA emphasizes cautious dose selection for elderly patients, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function 1
- ESRD patients typically require medication dosing adjustments, with increased intervals between doses rather than decreased individual doses being the preferred approach for renally-cleared medications 2
Critical Safety Considerations
- Hydroxyzine carries risk of QT prolongation and Torsade de Pointes, particularly in patients with pre-existing heart disease, electrolyte imbalances, or concomitant arrhythmogenic drug use 1
- ESRD patients frequently have cardiovascular comorbidities and electrolyte disturbances that increase this risk 3, 4
- Use with extreme caution in patients with risk factors for QT prolongation, including congenital long QT syndrome, recent myocardial infarction, uncompensated heart failure, and bradyarrhythmias 1
- Avoid concomitant use with other QT-prolonging medications (Class 1A/III antiarrhythmics, certain antipsychotics, antidepressants, and antibiotics) 1
Timing Considerations for Dialysis Patients
- While the FDA label does not provide specific guidance on dialysis timing for hydroxyzine, general principles for dialyzed medications suggest administering after dialysis sessions to prevent premature drug removal 2
- This approach prevents subtherapeutic levels that would occur if the drug were given before dialysis 2
Common Pitfalls to Avoid
- Do not use standard adult dosing without considering the patient's renal impairment and age 1
- Monitor closely for excessive sedation, confusion, and CNS depression, which are more common in ESRD patients 1, 4
- Avoid combining with other CNS depressants (narcotics, barbiturates, alcohol) without reducing their dosages, as hydroxyzine potentiates their effects 1
- Check for drug-drug interactions, as ESRD patients typically take multiple medications and DDIs are common in this population 4