Before you begin using a medication, be sure to inform your doctor of any medical 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 this medication.
Anemia: Macitentan may cause low levels of red blood cells. 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.
Kidney function: Kidney disease or reduced kidney function may cause this medication to build up in the body, causing side effects. If you have reduced kidney function or kidney disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Pregnancy: This medication may cause harm or death to the developing baby and mother if it is taken during pregnancy. Women must not become pregnant while taking macitentan or for at least one month after stopping the medication. Your doctor may routinely perform pregnancy tests while you are taking macitentan to confirm the safety of continuing to take this medication.
Women who may become pregnant must not be given macitentan until pregnancy is excluded. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if macitentan passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Women should not breast-feed while taking this medication.
Children: The safety and effectiveness of using this medication have not been established for children less than 18 years of age.