Key facts about Opsumit
What is Opsumit?
Opsumit is the brand name for macitentan and is available as an oral tablet.
What dosages is Opsumit available in?
Opsumit is available as a 10 mg oral tablet.
What is Opsumit used for?
- Opsumit is an endothelin receptor antagonist and is used to treat pulmonary arterial hypertension (PAH).
How does Opsumit work?
Opsumit is an endothelin receptor antagonist. It works by blocking the effects of a protein in your body called endothelin. Doing so relaxes the blood vessels that go from your heart to your lungs and allows more blood to flow through. This lowers the amount of work your heart needs to pump blood to your lungs to get oxygen for your body. As a result, it’s easier for you to exercise and breathe.
How do I take Opsumit?
- Opsumit is typically dosed as 10 mg by mouth once per day.
Is it safe for me to take Opsumit?
Opsumit is a safe and effective treatment when used for FDA licensed indications. However, like all medications, they may give you unwanted side effects. You should always discuss potential side effects with your physician to ensure the medication is suitable and right for you. You should not use this medication if you are pregnant.
Opsumit Common Side Effects
Common side effects of Opsumit:
- Cold-like symptoms or a sore throat
- Headache
- Anemia
- Bronchitis
- Urinary tract infection
- Flu
Opsumit Serious Side Effects
Serious side effects are rare with Opsumit. Contact your healthcare provider immediately if you experience any of the following.
- Liver problems: swelling of your stomach, yellowing of your skin or the whites of your eyes, confusion, dark or brown urine
- Fluid buildup in the body: shortness of breath; swelling in the legs, ankles, or feet; irregular heartbeat; chest pain; unable to exercise; tiredness; unusual weight gain
Effects of other drugs, drug classes and over-the-counter products on Opsumit
The following medications may interact with Opsumit:
- Strong CYP3A4 inducers (rifampin) reduce exposure to macitentan:
- avoid co-administration with Opsumit).
- Strong CYP3A4 inhibitors (ketoconazole, ritonavir) increase exposure
- to macitentan: avoid co-administration with Opsumit.
Who makes Opsumit?
Actelion Pharmaceuticals US, Inc.
Is Opsumit safe in pregnancy?
Opsumit should not be given to a pregnant female because
it may cause fetal harm. Females of reproductive potential: exclude pregnancy before start of treatment, monthly during treatment, and 1 month after stopping treatment. Prevent pregnancy during treatment and for one month after treatment by using acceptable methods of contraception. For all female patients, Opsumit is available only through a restricted program called the Opsumit Risk Evaluation and Mitigation Strategy (REMS).













