Drug Interactions between selegiline and sertraline

GENERALLY AVOID: Foods that contain large amounts of tyramine may precipitate a hypertensive crisis in patients treated with monoamine oxidase inhibitors (MAOIs). The mechanism is inhibition of MAO-A, the enzyme responsible for metabolizing exogenous amines such as tyramine in the gut 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. Although selegiline is considered a selective inhibitor of MAO-B, the selectivity may not be absolute even at recommended dosages. Rare cases of hypertensive reactions associated with ingestion of tyramine-containing foods have been reported in patients taking the recommended daily oral dose of selegiline. Data for transdermal selegiline indicate that the 6 mg/24 hour dosage may be given safely without dietary restrictions. However, limited data are available for higher dosages.

MANAGEMENT: Patients treated with oral selegiline and transdermal selegiline (greater than 6 mg/24 hour) should preferably avoid consumption of products that contain large amounts of amines and protein foods in which aging or breakdown of protein is used to increase flavor. These foods include cheese (particularly strong, aged or processed cheeses), sour cream, wine (particularly red wine), champagne, beer, pickled herring, anchovies, caviar, shrimp paste, liver (particularly chicken liver), dry sausage, salamis, figs, raisins, bananas, avocados, chocolate, soy sauce, bean curd, sauerkraut, yogurt, papaya products, meat tenderizers, fava bean pods, protein extracts, yeast extracts, and dietary supplements. Caffeine may also precipitate hypertensive crisis so its intake should be minimized as well. At least 14 days should elapse following discontinuation of selegiline therapy before these foods may be consumed. Specially designed reference materials and dietary consultation are recommended so that an appropriate and safe diet can be planned. Patients should also be advised to promptly seek medical attention if they experience potential signs and symptoms of a hypertensive crisis such as severe headache, visual disturbances, difficulty thinking, stupor or coma, seizures, chest pain, unexplained nausea or vomiting, and stroke-like symptoms. The recommended dosages of selegiline should not be exceeded, as it can increase the risk of nonselective MAO inhibition and a hypertensive crisis.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of sertraline. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills. In addition, limited clinical data suggest that consumption of grapefruit juice during treatment with sertraline may result in increased plasma concentrations of sertraline. The proposed mechanism is inhibition of CYP450 3A4-mediated metabolism by certain compounds present in grapefruit. An in-vitro study demonstrated that grapefruit juice dose-dependently inhibits the conversion of sertraline to its metabolite, desmethylsertraline. In a study with eight Japanese subjects, mean plasma levels of sertraline increased by approximately 100% and maximum plasma concentrations increased by 66% after the ingestion of three 250 mL glasses of grapefruit juice per day for 5 days and administration of a single dose of sertraline 75 mg on the sixth day. In another small study with 5 patients, mean sertraline trough levels increased by 47% after taking sertraline for at least 6 weeks, then taking sertraline with 240 mL grapefruit juice daily for 1 week. The clinical significance is unknown; 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 receiving sertraline should be advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how sertraline affects them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities. Some authorities recommend that consumption of grapefruit juice should be avoided during sertraline therapy.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of central nervous system (CNS)-active agents. Use in combination may result in additive CNS depression and/or impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Patients receiving CNS-active agents should be advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled against driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.