Drug Interactions between eszopiclone and Paxlovid
This report displays the potential drug interactions for the following 2 drugs:
- eszopiclone
- Paxlovid (nirmatrelvir/ritonavir)
Interactions between your drugs
ritonavir eszopiclone
Applies to: Paxlovid (nirmatrelvir / ritonavir) and eszopiclone
ADJUST DOSE: Coadministration with potent inhibitors of CYP450 3A4 may increase the plasma concentrations of both zopiclone and its pharmacologically active S(-) enantiomer, eszopiclone. Zopiclone has been shown in vitro to be metabolized by CYP450 3A4 and CYP450 2C8, while eszopiclone is primarily metabolized by CYP450 3A4 and 2E1 via demethylation and oxidation. In 18 healthy subjects, administration of a single 3 mg dose of eszopiclone with the potent CYP450 3A4 inhibitor ketoconazole (400 mg daily for 5 days) increased eszopiclone half-life, peak plasma concentration (Cmax) and systemic exposure (AUC) by 1.3-, 1.4- and 2.2-fold, respectively. In 10 healthy young subjects, itraconazole 200 mg daily given for 4 days increased the Cmax and AUC of a single 7.5 mg dose of zopiclone by 29% and 73%, respectively, and prolonged its half-life by 40%. The pharmacokinetics of eszopiclone were not reported in this study. A case report describes an 86-year-old woman who experienced morning drowsiness during coadministration of zopiclone and nefazodone, a known potent CYP450 3A4 inhibitor. Zopiclone plasma concentrations were measured both during and after withdrawal of nefazodone therapy. Following discontinuation of nefazodone due to lack of therapeutic effect, the plasma concentration of S(-) zopiclone decreased from 107 to 16.9 ng/mL, and that of R(+) zopiclone decreased from 20.6 to 1.45 ng/mL.
MANAGEMENT: Due to increased risk of next-day psychomotor impairment, the dosages of eszopiclone and zopiclone should be reduced when used with potent CYP450 3A4 inhibitors. The manufacturers recommend that total dose of eszopiclone not exceed 2 mg. An initial dose of 3.75 mg is recommended for zopiclone, which may be increased up to 5 mg if clinically indicated. Patients should be advised to avoid driving or operating hazardous machinery until they know how these medications affect them, preferably at least 12 hours after administration of the hypnotic.
References (7)
- Dresser GK, Spence JD, Bailey DG (2000) "Pharmacokinetic-pharmacodynamic consequences and clinical relevance of cytochrome P450 3A4 inhibition." Clin Pharmacokinet, 38, p. 41-57
- Becquemont L, Mouajjah S, Escaffre O, Beaune P, Funck-Bretano C, Jaillon P (1999) "Cytochrome P-450 3A4 and 2C8 are involved in zopiclone metabolism." Drug Metab Dispos, 27, p. 1068-73
- Alderman CP, Gebauer MG, Gilbert AL, Condon JT (2001) "Possible interaction of zopiclone and nefazodone." Ann Pharmacother, 35, p. 1378-80
- (2004) "Product Information. Lunesta (eszopiclone)." Sepracor Inc
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- Cerner Multum, Inc. "Australian Product Information."
- (2014) "Product Information. Imovane (zopiclone)." Rhone-Poulenc Rorer Canada Inc
Drug and food interactions
ritonavir food
Applies to: Paxlovid (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
eszopiclone food
Applies to: eszopiclone
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of zopiclone and eszopiclone. 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 eszopiclone (the S-enantiomer of zopiclone) with or immediately after a high-fat/heavy meal may delay the onset of hypnotic effects. In healthy adults, administration of a 3 mg dose of eszopiclone after a high-fat meal decreased the mean peak plasma drug concentration (Cmax) by 21% and delayed the time to reach peak plasma drug concentration (Tmax) by approximately 1 hour. Theoretically, this interaction should also affect racemic zopiclone.
MANAGEMENT: Patients receiving zopiclone or eszopiclone should be advised to avoid consumption of alcohol. For faster sleep onset, it may be advisable to not administer eszopiclone and zopiclone with or immediately after a high-fat/heavy meal.
References (2)
- (2004) "Product Information. Lunesta (eszopiclone)." Sepracor Inc
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
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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