Drug Interaction Report

Nafcillin may reduce the blood levels of upadacitinib, which may make the medication less effective in some cases. Contact your doctor if your symptoms worsen or your condition changes. 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.

Consumption of grapefruit, grapefruit juice, and supplements that contain grapefruit should be avoided during treatment with upadacitinib as they may increase the blood levels of upadacitinib, which may increase the risk and/or severity of side effects such as low blood cell counts, anemia, serious infections, and elevated blood lipid levels. Contact your doctor if you develop symptoms such as paleness, fatigue, dizziness, fainting, fever, chills, diarrhea, sore throat, muscle aches, shortness of breath, blood in phlegm, weight loss, red or inflamed skin, body sores, or pain or burning during urination.

Smoking during treatment with upadacitinib may increase your risk of serious cardiovascular events and of developing malignancies. Tell your doctor if you are a current or past smoker. Talk to your doctor if you have any questions or concerns. Get emergency help right away if you develop any symptoms of a heart attack or stroke during treatment with upadacitinib, including severe tightness, pain, pressure, or heaviness in your chest, neck, or jaw; weakness in one side of your body; slurred speech; shortness of breath or feeling lightheaded. 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 may experience reduced absorption of nafcillin in the presence of food. The effectiveness of the antibiotic may be reduced. Nafcillin should be administered one hour before or two hours after meals. This will make it easier for your body to absorb the medication. Penicillin V and amoxicillin are not affected by food and may be given without regard to meals.