Drug Interactions between ketoconazole and tofacitinib

You should avoid the use of alcohol while being treated with ketoconazole. Ketoconazole may cause liver damage and using it with alcohol or products containing alcohol may increase that risk. In addition, consumption of alcoholic beverages or products containing alcohol during treatment with ketoconazole may trigger a disulfiram-like reaction in some patients, with unpleasant symptoms such as flushing, palpitations, and nausea. Ketoconazole may be taken with or without food. You should avoid consumption of grapefruit, grapefruit juice, or any supplements that contain grapefruit extract during treatment with ketoconazole unless directed otherwise by your doctor. Grapefruit juice may increase the blood levels of ketoconazole. This may increase the risk and/or severity of side effects and liver problems. You should seek immediate medical attention if you develop signs and symptoms of liver damage during treatment with ketoconazole, such as joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, light colored stools, and yellowing of the skin or eyes. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Consumer information for this interaction is not currently available.

MONITOR: Grapefruit juice may increase the plasma concentrations of tofacitinib. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. The extent and clinical significance are unknown. Moreover, pharmacokinetic alterations associated with interactions involving grapefruit juice are often subject to a high degree of interpatient variability.

MANAGEMENT: Until more information is available, some authorities recommend avoiding consumption of grapefruit juice during tofacitinib therapy (Canada). Patients receiving tofacitinib therapy who ingest grapefruits or grapefruit juice should be monitored for adverse effects and undue fluctuations in plasma drug levels.