Before you begin using a medication, be sure to inform your doctor of any medication conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use Act Bosentan.
Anemia: Bosentan can reduce the number of red blood cells, which carry oxygen throughout your body. If you experience symptoms of reduced red blood cell count (anemia) such as shortness of breath, feeling unusually tired, or pale skin, contact your doctor as soon as possible.
Your doctor will periodically do blood work to monitor your red blood cell levels to ensure that this does not happen.
Heart failure: People with severe chronic heart failure may see a worsening of their condition when they first start bosentan. This may be due to fluid retention, which is one of the side effects of bosentan. If you have severe chronic heart failure, discuss with your doctor how Act Bosentan may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Act Bosentan, and whether any special monitoring is needed.
Liver problems: Bosentan can affect your liver. Your doctor will perform regular blood tests to make sure your liver is functioning properly. Bosentan should not be used by people who have moderately to severely reduced liver function.
If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.
Low blood pressure: If you have low blood pressure, discuss with your doctor how Act Bosentan may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Act Bosentan, and whether any special monitoring is needed.
Stopping medication: Suddenly stopping bosentan may worsen your symptoms. Do not stop taking Act Bosentan unless directed by your doctor. If you are stopping treatment, your doctor will monitor you and reduce the dose over a period of time before stopping the medication completely.
Pregnancy: The medication should not be used during pregnancy, as it may cause serious harm to the fetus. Your doctor should perform a pregnancy test before you start Act Bosentan, and monthly thereafter while you are taking Act Bosentan. Since bosentan decreases the effectiveness of hormonal birth control, you should use more than one form of contraception (e.g., non-hormonal forms such as condoms) while taking Act Bosentan. If you become pregnant while taking Act Bosentan, contact your doctor immediately.
Breast-feeding: It is not known if bosentan passes into breast milk. If you are a breast-feeding mother and are taking Act Bosentan, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using Act Bosentan for children are not well established. Your doctor will determine if the benefits of the medication outweigh the risks for your child.
Seniors: People over 65 years old may be more at risk of side effects from Act Bosentan due to age-related decreases in liver function.
