Drug Interactions between allopurinol and hydromorphone

GENERALLY AVOID: Alcohol may potentiate the central nervous system (CNS) depressant effects of opioid analgesics including hydromorphone. Concomitant use may result in additive CNS depression and impairment of judgment, thinking, and psychomotor skills. In more severe cases, hypotension, respiratory depression, profound sedation, coma, or even death may occur.

GENERALLY AVOID: Consumption of alcohol while taking sustained-release formulations of hydromorphone may cause rapid release of the drug, resulting in high systemic levels of hydromorphone that may be potentially lethal even in opioid-tolerant patients. Alcohol appears to disrupt the extended release mechanism, causing 'dose-dumping' into the bloodstream. In 48 healthy volunteers, coadministration of a 12 mg dose of sustained-release hydromorphone with 240 mL of 40% (80 proof) alcohol resulted in a mean peak hydromorphone concentration (Cmax) approximately six times greater than when taken with water. One subject had a 16-fold increase in hydromorphone Cmax with 40% alcohol compared to water. In some subjects, coadministration with 8 ounces of 4% alcohol (equivalent to 2/3 of a typical serving of beer) resulted in almost twice the hydromorphone Cmax than when coadministered with water. The effect of alcohol was more pronounced in a fasted state.

MANAGEMENT: Patients taking sustained-release formulations of hydromorphone should not consume alcohol or use medications that contain alcohol on days of hydromorphone dosing. In general, potent narcotics such as hydromorphone should not be combined with alcohol.

ADJUST DOSING INTERVAL: The tolerability of allopurinol may be improved by giving it after a meal. Additionally, when the dose is greater than 300 mg, dividing the total daily dose into smaller doses administered more often may be appropriate to help minimize gastrointestinal irritation.

MONITOR: Concomitant use of allopurinol with central nervous system (CNS) depressants, including alcohol, may potentiate adverse effects such as somnolence and sedation.

MANAGEMENT: To improve tolerability, some manufacturers suggest administering allopurinol after a meal. Additionally, if the daily dose is greater than 300 mg, administering allopurinol in divided doses may help reduce gastrointestinal intolerance. Patients should also be counseled to avoid or limit consumption of alcohol and to avoid activities requiring mental alertness such as driving or operating hazardous machinery until they know how the medication affects them.