Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration of momelotinib may increase the plasma concentrations and effects of drugs that are substrates of the P-glycoprotein (P-gp) efflux transporter. The proposed mechanism is increased exposure of the P-gp substrate due to inhibition of intestinal P-gp efflux transporter. However, clinical data are not available.

MANAGEMENT: Caution is recommended with the concomitant use of momelotinib and P-gp substrates, particularly those with a narrow therapeutic index. Dosage adjustments as well as clinical and laboratory monitoring should be considered whenever momelotinib is added to or withdrawn from therapy with these drugs. Individual product labeling for the coadministered drug may also be consulted for specific guidance.

Do not consume grapefruit or grapefruit juice during treatment with levomethadyl acetate unless directed otherwise by your doctor. Grapefruit juice may increase the blood levels of levomethadyl acetate. This can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. You may be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). You should also avoid alcohol during treatment, as it may add to the central nervous system effects of levomethadyl acetate and increase the risk of serious side effects such as respiratory depression, low blood pressure, fainting, coma, and even death. Do not drive, operate machinery, or perform other hazardous activities until you know how the medication affects you. Talk to your doctor if you have any questions or concerns. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment. 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.