Drug Interaction Report

Ritonavir may increase the blood levels of the active medication in enfortumab vedotin. This may increase the risk and/or severity of side effects such as nausea; vomiting; diarrhea; loss of appetite; tingling, numbness or burning in the hands and feet; muscle weakness; hyperglycemia (high blood sugar); skin reactions (rash, itching, hair loss); lung problems (trouble breathing, shortness of breath, cough); eye disorders (dry eyes, inflammation of the cornea, blurred vision); and low platelet and white blood cell counts. You may also be more likely to develop bleeding problems or infections due to low blood cell counts. 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. 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.

Ritonavir should be taken with food to lessen gastrointestinal side effects. It is important that you take this medication exactly as prescribed by your doctor. Do not change your treatment or stop treatment without first talking to your doctor.

Food may affect the absorption of lopinavir-ritonavir (brand name Kaletra) depending on whether you are taking the oral solution or the tablet. The oral solution should be taken with food to enhance absorption and help it work better. The tablet formulation can be take with or without food. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. 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.