Read the Medication Guide and, if available, the Patient Information Leaflet provided by your pharmacist before you start taking macitentan and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor, usually once daily. Swallow the tablet whole. Do not split, crush, or chew the tablet.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.

Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase.

Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.

Tell your doctor if your condition does not improve or if it worsens.