Opsumit

Brand Name

Opsumit

Common Name

macitentan

In this drug factsheet:

• How does this medication work? What will it do for me?
• How should I use this medication?
• What form(s) does this medication come in?
• Who should NOT take this medication?
• What side effects are possible with this medication?
• Are there any other precautions or warnings for this medication?
• What other drugs could interact with this medication?

How does this medication work? What will it do for me?

Macitentan belongs to the class of medications called endothelin receptor antagonists. It is used alone and in combination with other medications to treat pulmonary arterial hypertension (PAH). PAH is a condition in which there is high blood pressure in the blood vessels of the lungs that lead to the heart. In pulmonary hypertension, the blood vessels become narrowed or blocked, making it harder for the blood to flow through the lungs and makes the heart work harder to pump blood through the lungs. Macitentan reduces the blood pressure in your lungs, allowing your heart to pump more efficiently.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

How should I use this medication?

The recommended adult dose of macitentan is 10 mg taken once daily. This medication may be taken with food or on an empty stomach. Swallow the tablets whole with some water. Do not crush, break or chew the tablets.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

It is important that this medication be taken exactly as prescribed by your doctor.

If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

What form(s) does this medication come in?

Each round, bi-convex, film-coated tablet, debossed with "10" on both sides, contains 10 mg of macitentan. Nonmedicinal ingredients: lactose monohydrate, magnesium stearate, microcrystalline cellulose, polysorbate 80, povidone, sodium starch glycolate Type A, polyvinyl alcohol, soya lecithin, talc, titanium dioxide, and xanthan gum.

Who should NOT take this medication?

Do not take macitentan if you:

• are allergic to macitentan or any ingredients of the medication
• are pregnant or may become pregnant
• are breast-feeding

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• flu-like symptoms (sudden lack of energy, fever, cough, sore throat)
• headache
• persistent cough
• stuffy nose

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• irritation of the airways (bronchitis)
• signs of low blood pressure (e.g., dizziness, lightheadedness, or fainting, especially when getting up from a lying or sitting position)
• signs of low red blood cells or anemia (e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
• signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
• symptoms of a urinary tract infection (e.g., painful urination, frequency, urgency, pressure in the lower pelvis, fever)
• unusual swelling of the hands, legs, feet, or ankles

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

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.

Fertility: Taking macitentan may cause decreased sperm production and impaired fertility. It is not clear if fertility returns after stopping the medication. Talk to your doctor about options if this is a concern.

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.

Liver function: Macitentan may reduce liver function. If you have liver problems, 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. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication. People with severely reduced liver function should not use this medication.

Macitentan has also been reported to cause liver damage. 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.

Pregnancy: This medication may cause harm or death to your developing baby and to you if you take it while pregnant. You 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.

People who may become pregnant must not take macitentan until pregnancy is ruled out. 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 breast-feeding and are taking this medication, it may affect your baby. You 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.

What other drugs could interact with this medication?

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

All material copyright MediResource Inc. 1996 – 2025. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/Opsumit