Drug Interactions between fezolinetant and IsonaRif

Using isoniazid together with rifAMPin can cause serious side effects that may affect your liver. You should avoid or limit the use of alcohol while being treated with these medications. Your doctor may already be aware of the risks but has determined that this is the best course of treatment for you, has taken appropriate precautions, and is monitoring you closely for any potential complications. If you develop severe liver problems, you may need a dose adjustment or an interruption in therapy. Call your doctor immediately if you have fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, abdominal pain, dark colored urine, light colored stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. Talk to your healthcare provider 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.

CONTRAINDICATED: Coadministration with inhibitors of CYP450 1A2 may significantly increase the plasma concentrations of fezolinetant, which is primarily metabolized by the isoenzyme. In clinical drug interaction studies, coadministration of the potent CYP450 1A2 inhibitor fluvoxamine increased the peak plasma concentration (Cmax) and systemic exposure (AUC) by 80% and 840%, respectively. Likewise, the moderate CYP450 1A2 inhibitor, mexiletine, is predicted through physiologically based pharmacokinetic (PBPK) modeling to increase the Cmax and AUC of fezolinetant by 40% and 360%, respectively. The weak CYP450 1A2 inhibitor cimetidine is also predicted via PBPK to increase the Cmax and AUC of fezolinetant by 30% and 100%, respectively.

MANAGEMENT: Concomitant use of fezolinetant with CYP450 1A2 inhibitors is considered contraindicated.

RifAMPin may cause liver problems and using it with other medications that can also affect the liver, such as fezolinetant, may increase that risk. You should avoid or limit the use of alcohol while being treated with these medications. Your doctor may already be aware of the risks but has determined that this is the best course of treatment for you, has taken appropriate precautions, and is monitoring you closely for any potential complications. If you develop severe liver problems, you may need a dose adjustment or an interruption in therapy. Call your doctor immediately if you have fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, abdominal pain, dark colored urine, light colored stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. Talk to your healthcare provider 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.