Drug Interactions between droperidol / fentanyl and ozanimod

GENERALLY AVOID: Alcohol may potentiate the central nervous system (CNS) depressant effects of opioid analgesics including fentanyl. Concomitant use may result in additive CNS depression and impairment of judgment, thinking, and psychomotor skills. In more severe cases, hypotension, respiratory depression, profound sedation, coma, or even death may occur.

GENERALLY AVOID: Consumption of grapefruit juice during treatment with oral transmucosal formulations of fentanyl may result in increased plasma concentrations of fentanyl, which is primarily metabolized by CYP450 3A4 isoenzyme in the liver and intestine. Certain compounds present in grapefruit are known to inhibit CYP450 3A4 and may increase the bioavailability of swallowed fentanyl (reportedly up to 75% of a dose) and/or decrease its systemic clearance. The clinical significance is unknown. In 12 healthy volunteers, consumption of 250 mL regular-strength grapefruit juice the night before and 100 mL double-strength grapefruit juice one hour before administration of oral transmucosal fentanyl citrate (600 or 800 mcg lozenge) did not significantly affect fentanyl pharmacokinetics, overall extent of fentanyl-induced miosis (miosis AUC), or subjective self-assessment of various clinical effects compared to control. However, pharmacokinetic alterations associated with interactions involving grapefruit juice are often subject to a high degree of interpatient variability. The possibility of significant interaction in some patients should be considered.

MANAGEMENT: Patients should not consume alcoholic beverages or use drug products that contain alcohol during treatment with fentanyl. Any history of alcohol or illicit drug use should be considered when prescribing fentanyl, and therapy initiated at a lower dosage if necessary. Patients should be closely monitored for signs and symptoms of sedation, respiratory depression, and hypotension. Due to a high degree of interpatient variability with respect to grapefruit juice interactions, patients treated with fentanyl should preferably avoid the consumption of grapefruit and grapefruit juice. In addition, patients receiving transdermal formulations of fentanyl should be cautioned that drug interactions and drug effects may be observed for a prolonged period beyond removal of the patch, as significant amounts of fentanyl are absorbed from the skin for 17 hours or more after the patch is removed.

MONITOR CLOSELY: The use of droperidol has been associated with QT interval prolongation, torsade de pointes and other serious arrhythmias, and sudden death. The concurrent administration of agents that can produce hypokalemia and/or hypomagnesemia (e.g., potassium-wasting diuretics, amphotericin B, cation exchange resins), drugs known to increase the QT interval (e.g., phenothiazines, tricyclic antidepressants, antiarrhythmic agents, etc.), certain other drugs (benzodiazepines, volatile anesthetics, intravenous opiates), or alcohol abuse may increase the risk of prolonged QT syndrome. In addition, central nervous system- and/or respiratory-depressant effects may be additively or synergistically increased in patients taking droperidol with certain other drugs that cause these effects, especially in elderly or debilitated patients.

MANAGEMENT: The manufacturer recommends extreme caution if droperidol must be given concomitantly with these agents. The dosage of droperidol should be individualized and titrated to the desired effect. Routine vital sign and ECG monitoring is recommended. When droperidol is used in combination with other drugs that cause CNS and/or respiratory depression, patients should be monitored for potentially excessive or prolonged CNS and respiratory depression. Ambulatory patients should be counseled to avoid hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their doctor if they experience excessive or prolonged CNS effects that interfere with their normal activities.

GENERALLY AVOID: Foods that contain large amounts of tyramine may precipitate a hypertensive crisis in patients treated with ozanimod. The proposed mechanism involves potentiation of the tyramine pressor effect due to inhibition of monoamine oxidase (MAO) by the major active metabolites of ozanimod, CC112273 and CC1084037. Monoamine oxidase in the gastrointestinal tract and liver, primarily type A (MAO-A), is the enzyme responsible for metabolizing exogenous amines such as tyramine and preventing them from being absorbed intact. Once absorbed, tyramine is metabolized to octopamine, a substance that is believed to displace norepinephrine from storage granules causing a rise in blood pressure. In vitro, CC112273 and CC1084037 inhibited MAO-B (IC50 values of 5.72 nM and 58 nM, respectively) with more than 1000-fold selectivity over MAO-A (IC50 values >10000 nM). Because of this selectivity, as well as the fact that free plasma concentrations of CC112273 and CC1084037 are less than 8% of the in vitro IC50 values for MAO-B inhibition, ozanimod is expected to have a much lower propensity to cause hypertensive crises than nonselective MAO inhibitors. However, rare cases of hypertensive crisis have occurred during clinical trials for the treatment of multiple sclerosis (MS) and ulcerative colitis (UC) and in postmarketing use. In controlled clinical trials, hypertension and blood pressure increases were reported more frequently in patients treated with ozanimod (up to 4.6% in MS patients receiving ozanimod 0.92 mg/day) than in patients treated with interferon beta-1a (MS) or placebo (UC).

Administration of ozanimod with either a high-fat, high-calorie meal (1000 calories; 50% fat) or a low-fat, low-calorie meal (300 calories; 10% fat) had no effects on ozanimod peak plasma concentration (Cmax) and systemic exposure (AUC) compared to administration under fasted conditions.

MANAGEMENT: Dietary restriction is not ordinarily required during ozanimod treatment with respect to most foods and beverages that contain tyramine, which usually include aged, fermented, cured, smoked, or pickled foods (e.g., air-dried and fermented meats or fish, aged cheeses, most soybean products, yeast extracts, red wine, beer, sauerkraut). However, certain foods like some of the aged cheeses (e.g., Boursault, Liederkrantz, Mycella, Stilton) and pickled herring may contain very high amounts of tyramine and could potentially cause a hypertensive reaction in patients taking ozanimod, even at recommended dosages, due to increased sensitivity to tyramine. Patients should be advised to avoid the intake of very high levels of tyramine (e.g., greater than 150 mg) and to promptly seek medical attention if they experience potential signs and symptoms of a hypertensive crisis such as severe headache, visual disturbances, confusion, stupor, seizures, chest pain, unexplained nausea or vomiting, and stroke-like symptoms. Blood pressure should be regularly monitored and managed accordingly. Because of the long elimination half-lives of the major active metabolites, these precautions may need to be observed for up to 3 months following the last ozanimod dose. Ozanimod can be administered with or without food.

MONITOR: Smoking cessation may lead to elevated plasma concentrations and enhanced pharmacologic effects of drugs that are substrates of CYP450 1A2 (and possibly CYP450 1A1) and/or certain drugs with a narrow therapeutic index (e.g., flecainide, pentazocine). One proposed mechanism is related to the loss of CYP450 1A2 and 1A1 induction by polycyclic aromatic hydrocarbons in tobacco smoke; when smoking cessation agents are initiated and smoking stops, the metabolism of certain drugs may decrease leading to increased plasma concentrations. The mechanism by which smoking cessation affects narrow therapeutic index drugs that are not known substrates of CYP450 1A2 or 1A1 is unknown. The clinical significance of this interaction is unknown as clinical data are lacking.

MANAGEMENT: Until more information is available, caution is advisable if smoking cessation agents are used concomitantly with drugs that are substrates of CYP450 1A2 or 1A1 and/or those with a narrow therapeutic range. Patients receiving smoking cessation agents may require periodic dose adjustments and closer clinical and laboratory monitoring of medications that are substrates of CYP450 1A2 or 1A1.