Drug Interactions between dronabinol and GaviLyte-H

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

GENERALLY AVOID: Grapefruit and/or grapefruit juice may increase the plasma concentrations and effects of drugs that are substrates of the CYP450 3A4 isoenzyme. The proposed mechanism is inhibition of CYP450 3A4 mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Inhibition of hepatic CYP450 3A4 may also contribute. Because pharmacokinetic interactions involving grapefruit juice are often subject to a high degree of interpatient variability, the extent to which a given patient may be affected is difficult to predict.

MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit the consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete 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. It may be advisable for patients to avoid consumption of grapefruit, grapefruit juice, or supplements that contain grapefruit during treatment with drugs that undergo metabolism by CYP450 3A4. Orange juice is not expected to interact with these drugs.

ADJUST DOSING INTERVAL: Bowel cleansing products can increase the gastrointestinal transit rate. Oral medications administered within one hour of the start of administration of the bowel cleansing solution may be flushed from the gastrointestinal tract and not properly absorbed.

MANAGEMENT: Patients should be advised that absorption of oral medications may be impaired during bowel cleansing treatment. Oral medications (e.g., anticonvulsants, oral contraceptives, antidiabetic agents, antibiotics) should not be administered during and within one hour of starting bowel cleansing treatment whenever possible. However, if concomitant use cannot be avoided, monitoring for reduced therapeutic effects may be advisable.