Drug Interaction Report

MONITOR: Coadministration with alcohol or other central nervous system (CNS) depressants may enhance the sedative effects of allopurinol and increase the likelihood and/or severity of central nervous system (CNS) side effects, such as drowsiness, somnolence, vertigo, and ataxia.

MANAGEMENT: Caution for increased CNS adverse effects is advised if allopurinol is coadministered with alcohol, other CNS depressants, or agents that cause dizziness or vertigo. Patients should not drive, operate machinery, or engage in hazardous activities requiring mental alertness and motor coordination until they know how the medications affect them.

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.

GENERALLY AVOID: Risperidone oral solution is not compatible with either tea or cola. In addition, alcohol may potentiate some of the pharmacologic effects of risperidone. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Risperidone oral solution should not be mixed with tea or cola. It may be taken with water, coffee, orange juice, or lowfat milk. Patients should also be advised to avoid consumption of alcohol.