Drug Interactions between BuSpar and voriconazole
This report displays the potential drug interactions for the following 2 drugs:
- BuSpar (buspirone)
- voriconazole
Interactions between your drugs
busPIRone voriconazole
Applies to: BuSpar (buspirone) and voriconazole
MONITOR: Coadministration with voriconazole may increase the plasma concentrations of drugs that are substrates of CYP450 2C19, 2C9, and/or 3A4. The mechanism is decreased clearance due to inhibition of those isoenzymes by voriconazole. Increased plasma levels and/or pharmacologic effects of drugs such as cyclosporine, sirolimus, tacrolimus (3A4 substrates), and warfarin (2C9 substrate) have been reported during coadministration with voriconazole.
MANAGEMENT: Caution is advised if voriconazole must be used concomitantly with medications that undergo metabolism by CYP450 2C19, 2C9 and/or 3A4, particularly those with a narrow therapeutic range. Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs whenever voriconazole is added to or withdrawn from therapy. The manufacturer specifically recommends that a dosage reduction be considered for benzodiazepines, statins, long-acting opiates, and vinca alkaloids that are metabolized by the affected isoenzymes when used with voriconazole.
References (3)
- (2002) "Product Information. VFEND (voriconazole)." Pfizer U.S. Pharmaceuticals
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- Cerner Multum, Inc. "Australian Product Information."
Drug and food interactions
busPIRone food
Applies to: BuSpar (buspirone)
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of buspirone. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.
ADJUST DOSING INTERVAL: In a small, randomized, crossover study, the consumption of large amounts of grapefruit juice (compared to water) was associated with significantly increased plasma buspirone concentrations, slightly prolonged elimination half-lives, and delayed times to reach peak drug concentration. The perceived pharmacodynamic effect of buspirone, as measured by subjective drowsiness and overall subjective drug effect, was also enhanced by grapefruit juice. These alterations may stem from the delay of gastric emptying as well as inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall induced by certain compounds present in grapefruits.
MANAGEMENT: Patients receiving buspirone should be advised to avoid consumption of alcohol. Patients also should preferably avoid the consumption of large amounts of grapefruits and grapefruit juice to prevent any undue fluctuations in plasma drug levels. If this is not possible, the buspirone dose should be taken at least 2 hours before or 8 hours after grapefruit or grapefruit juice. Monitoring for increased CNS depression is recommended.
References (3)
- (2002) "Product Information. Buspar (buspirone)." Bristol-Myers Squibb
- Lilja JJ, Kivisto KT, Backman JT, Lamberg TS, Neuvonen PJ (1998) "Grapefruit juice substantially increases plasma concentrations of buspirone." Clin Pharmacol Ther, 64, p. 655-60
- Bailey DG, Dresser GR, Kreeft JH, Munoz C, Freeman DJ, Bend JR (2000) "Grapefruit-felodipine interaction: Effect of unprocessed fruit and probable active ingredients." Clin Pharmacol Ther, 68, p. 468-77
voriconazole food
Applies to: voriconazole
ADJUST DOSING INTERVAL: Food reduces the oral absorption and bioavailability of voriconazole. According to the product labeling, administration of multiple doses of voriconazole with high-fat meals decreased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) by 34% and 24%, respectively, when the drug is administered as a tablet, and by 58% and 37%, respectively, when administered as the oral suspension.
MANAGEMENT: To ensure maximal oral absorption, voriconazole tablets and oral suspension should be taken at least one hour before or after a meal.
References (2)
- (2002) "Product Information. VFEND (voriconazole)." Pfizer U.S. Pharmaceuticals
- Wohlt PD, Zheng L, Gunderson S, Balzar SA, Johnson BD, Fish JT (2009) "Recommendations for the use of medications with continuous enteral nutrition." Am J Health Syst Pharm, 66, p. 1438-67
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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