See More

What is OPSUMIT®?

OPSUMIT® is a prescription medicine used to treat pulmonary arterial hypertension (PAH, WHO Group 1). PAH is high blood pressure in the arteries of your lungs. OPSUMIT® can:

The most important information about OPSUMIT® (macitentan)

Do not take OPSUMIT® if you are pregnant or trying to get pregnant. OPSUMIT® can cause serious birth defects if taken while pregnant.

Women who are able to get pregnant must have negative pregnancy tests:

PAH Symptoms and Diagnosis

The most common PAH symptoms*



Feeling tired/worn out

Shortness of breath

Chest pain/discomfort

Swollen abdomen

Swelling in the legs/ankles

*OPSUMIT® (macitentan) has not been shown to improve all of the symptoms of PAH. Individual results may vary. Individual symptoms, situations, and circumstances may vary. Consult your healthcare team regarding your condition and appropriate medical treatment. The information provided is not intended to be used for medical diagnosis or treatment, or as a substitute for professional medical advice.

How is PAH diagnosed?

PAH diagnosis can be challenging because symptoms are often similar to other conditions affecting the lungs and heart. Doctors start by ruling out other diseases and then perform tests to diagnose PAH.

To confirm your PAH diagnosis and rule out other conditions, your PAH healthcare provider will determine what tests are needed. These tests may include the following:

Diagnostic Tests

Echo Cardiogram

Echocardiogram (Echo)

Echocardiogram (Echo)

An echocardiogram is a type of ultrasound that shows the size, shape, and function of your heart.


Lung scan (VQ scan)

Lung scan (VQ scan)

A lung scan, also called a ventilation/perfusion or VQ scan, is used to measure air and blood flow in your lungs.

Person with cough

Pulmonary function test (PFT)

Pulmonary function test (PFT)

A pulmonary function test is a breathing test that measures how well your lungs work.

Heart Icon with tube attached

Right heart

Right heart catheterization

A right heart catheterization is used to measure pressures in the heart and the arteries in your lungs.