Drug Interaction Report

Diagnostic testing with coccidioidin skin test can sometimes cause severe, even potentially life-threatening allergic reactions that require emergency treatment with epinephrine and medications like penbutolol can interfere with the body's response to these emergency treatments and potentially reduce their effectiveness. Talk to your doctor if you have any questions or concerns. Seek immediate medical attention if signs or symptoms of an allergic reaction develop after receiving coccidioidin skin test such as trouble breathing, swallowing, or speaking; throat tightness or swelling; dizziness, lightheadedness, or fainting; rapid or weak heartbeat; severe stomach cramps or pain; vomiting or diarrhea; and/or severe flushing or itching. 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.

Penbutolol and ethanol (alcohol) may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. These side effects are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. 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.

Using penbutolol together with multivitamin with minerals may decrease the effects of penbutolol. Separate the administration times of penbutolol and multivitamin with minerals by at least 2 hours. If your doctor does prescribe these medications together, you may need a dose adjustment or special test 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.