Drug Interactions between nirmatrelvir / ritonavir and ramelteon
This report displays the potential drug interactions for the following 2 drugs:
- nirmatrelvir/ritonavir
- ramelteon
Interactions between your drugs
ritonavir ramelteon
Applies to: nirmatrelvir / ritonavir and ramelteon
MONITOR: Coadministration with potent inhibitors of CYP450 3A4 and/or 2C9 may increase the plasma concentrations and pharmacologic effects of ramelteon, which is partially metabolized by these isoenzymes. In healthy volunteers, administration of a single 16 mg oral dose of ramelteon following pretreatment with the potent CYP450 3A4 inhibitor ketoconazole (200 mg orally twice daily for 4 days) increased ramelteon peak plasma concentration (Cmax) by 36% and systemic exposure (AUC) by 84% compared to administration of ramelteon alone. Likewise, coadministration with fluconazole, a potent CYP450 2C9 inhibitor, resulted in an increase of approximately 150% in the Cmax and AUC of ramelteon following a single 16 mg oral dose. Similar pharmacokinetic changes were also observed with its biologically active metabolite, known as M-II.
MANAGEMENT: Caution is advised if ramelteon is prescribed in combination with potent inhibitors of CYP450 3A4 (e.g., itraconazole, ketoconazole, posaconazole, voriconazole, conivaptan, delavirdine, nefazodone, protease inhibitors, ketolide and certain macrolide antibiotics) and/or CYP450 2C9 (e.g., fluconazole, gemfibrozil, imatinib, miconazole). A reduction in the ramelteon dosage may be necessary in patients who experience excessive sedation.
References (1)
- (2005) "Product Information. Rozerem (ramelteon)." Takeda Pharmaceuticals America
Drug and food interactions
ritonavir food
Applies to: nirmatrelvir / ritonavir
ADJUST DOSING INTERVAL: Administration with food may modestly affect the bioavailability of ritonavir from the various available formulations. When the oral solution was given under nonfasting conditions, peak ritonavir concentrations decreased 23% and the extent of absorption decreased 7% relative to fasting conditions. Dilution of the oral solution (within one hour of dosing) with 240 mL of chocolate milk or a nutritional supplement (Advera or Ensure) did not significantly affect the extent and rate of ritonavir absorption. When a single 100 mg dose of the tablet was administered with a high-fat meal (907 kcal; 52% fat, 15% protein, 33% carbohydrates), approximately 20% decreases in mean peak concentration (Cmax) and systemic exposure (AUC) were observed relative to administration after fasting. Similar decreases in Cmax and AUC were reported when the tablet was administered with a moderate-fat meal. In contrast, the extent of absorption of ritonavir from the soft gelatin capsule formulation was 13% higher when administered with a meal (615 KCal; 14.5% fat, 9% protein, and 76% carbohydrate) relative to fasting.
MANAGEMENT: Ritonavir should be taken with meals to enhance gastrointestinal tolerability.
References (1)
- (2001) "Product Information. Norvir (ritonavir)." Abbott Pharmaceutical
ramelteon food
Applies to: ramelteon
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of ramelteon. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.
ADJUST DOSING INTERVAL: Administration of ramelteon with or immediately after a high-fat/heavy meal may delay the onset of hypnotic effects. In study subjects, administration of a 16 mg dose of ramelteon with a high-fat meal decreased the peak plasma drug concentration (Cmax) by 22% and delayed the median time to reach peak plasma drug concentration (Tmax) by approximately 45 minutes compared to administration in a fasted state.
MANAGEMENT: Patients receiving ramelteon should be advised to avoid the consumption of alcohol. For faster sleep onset, ramelteon should not be administered with or immediately after a high-fat/heavy meal.
References (1)
- (2005) "Product Information. Rozerem (ramelteon)." Takeda Pharmaceuticals America
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
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