Drug Interaction Report

GENERALLY AVOID: Grapefruit juice may significantly increase the plasma concentrations of naloxegol. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. In pharmacokinetic studies, naloxegol systemic exposure (AUC) was increased approximately 3.5-fold by the moderate CYP450 3A4 inhibitor diltiazem and nearly 13-fold by the potent inhibitor ketoconazole. The interaction has not been studied with grapefruit juice. In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Increased exposure to naloxegol may precipitate opioid withdrawal symptoms such as hyperhidrosis, lacrimation, rhinorrhea, chills, diarrhea, abdominal pain, anxiety, insomnia, irritability, restlessness, and yawning.

ADJUST DOSING INTERVAL: Food may increase the rate and extent of naloxegol absorption. When administered with a high-fat meal, naloxegol peak plasma concentration (Cmax) and systemic exposure (AUC) increased by approximately 30% and 45%, respectively. In clinical trials, naloxegol was given on an empty stomach approximately 1 hour prior to the first meal in the morning.

MANAGEMENT: Patients treated with naloxegol should avoid consumption of grapefruit and grapefruit juice. Naloxegol should be taken on an empty stomach at least 1 hour prior to the first meal of the day or 2 hours after the meal.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of zolpidem. 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 zolpidem with food may delay the onset of hypnotic effects. In 30 healthy subjects, administration of zolpidem 20 minutes after a meal resulted in decreased mean peak plasma drug concentration (Cmax) and area under the concentration-time curve (AUC) by 25% and 15%, respectively, compared to fasting. The time to reach peak plasma drug concentration (Tmax) was prolonged by 60%, from 1.4 to 2.2 hours.

MANAGEMENT: Patients receiving zolpidem should be advised to avoid the consumption of alcohol. For faster sleep onset, zolpidem should not be administered with or immediately after a meal.