Drug Interaction Report

Blood levels and effects of ambrisentan may increase during the first few days of treatment with rifAMPin. This can increase the risk of serious side effects such as liver damage, anemia, and fluid accumulation (particularly in the lungs). You may need more frequent monitoring by your doctor for several days if you have been using ambrisentan and are starting treatment with rifAMPin. Contact your doctor immediately if you experience fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. Also seek medical attention if you develop paleness, dizziness, fainting, swelling, unusual weight gain, difficulty breathing, and/or shortness of breath. 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.

Food can decrease the levels of rifAMPin in your body. Taking rifAMPin on an empty stomach (at least 30 minutes before or 2 hours after a meal) will make it easier for your body to absorb the medication. Avoid drinking alcohol while taking rifAMPin because alcohol use may increase the risk of damage to your liver. It is important to seek immediate medical care if you experience any severe side effects or symptoms of liver damage such as fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, and/or yellowing of the skin or eyes. 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.