Drug Interaction Report

Using dofetilide together with trimethoprim is not recommended. Combining these medications may significantly increase the blood levels of dofetilide. High blood levels of dofetilide can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening. 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. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with dofetilide. 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.

Information for this minor interaction is available on the professional version.

Ask your doctor before using sulfamethoxazole together with ethanol (alcohol). Contact your doctor if you experience unpleasant side effects such as fast heartbeats, warmth or redness under your skin, tingly feeling, nausea, or vomiting. If you experience these side effects, you may need to avoid ethanol (alcohol) while taking sulfamethoxazole. You should check your food and medicine labels to see if these products contain ethanol (alcohol). 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.

Information for this minor interaction is available on the professional version.