Drug Interaction Report

Using mobocertinib together with histrelin can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a 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). Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone. 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.

You should avoid consumption of grapefruit and grapefruit juice during treatment with mobocertinib. Grapefruit juice can increase the blood levels of mobocertinib. This may increase the risk of side effects such as diarrhea, nausea, vomiting, rash, fatigue, musculoskeletal pain, mouth sores and inflammation, heart failure, and rare but potentially serious and life-threatening irregular heart rhythm disorders. 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.