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Drug Class: Commonly Known As: Category:
Endothelin Receptor Antagonist Opsumit Adult

Macitentan - What is it for

Macitentan is used to treat pulmonary arterial hypertension.

Every individual may respond to treatment in different ways. It is important that patients have realistic expectations of what the treatment can do.

It lowers the pressure in the pulmonary arteries (the blood vessels that transfer oxygen from the lungs to the blood) by blocking the effects of endothelin. It may have the potential to reverse some of the damage done by the condition. This should also improve symptoms such as breathlessness and increase your ability to exercise.

Macitentan - Side Effects, Precautions, and Contraindications

What side effects can Macitentan cause?

  • Macitentan may cause flushing, low blood pressure, fainting or headache. These may improve or go away with time. To reduce giddiness when changing position, rise slowly from a sitting or lying position.
  • Macitentan may cause anaemia (low haemoglobin level). Regular blood tests will be scheduled to monitor this.
  • Macitentan may cause changes in liver enzymes. Although these are not usually significant, you will need frequent blood tests to monitor your liver function. Inform your Cardiologist, Nurse and/or Pharmacist if you have signs of liver problems like dark urine, increased tiredness, loss of appetite, light- coloured stools, vomiting, yellow skin or eyes.
  • Rarely, Macitentan may cause leg oedema (swelling). Inform your Cardiologist, Nurse or Pharmacist if you experience this.
  • If you experience flu-like symptoms (for example, nose and throat irritation or stuffy nose), or may have urinary tract infection (trouble or pain passing urine), inform your Cardiologist or Nurse.

Before taking Macitentan, what precautions must I follow?

Please inform your doctor if you are pregnant before starting this medicine.

What food or medicine must I avoid when I take Macitentan?

  • Macitentan may interact with certain antibiotics and antifungal medications taken by mouth. Please consult the Pulmonary Hypertension team if you are started on any of these.
  • Inform your Cardiologist, Nurse and/or Pharmacist if you are taking any other over-the- counter (OTC) medications, health/herbal supplements or traditional medications. The Pulmonary Hypertension Team will check to ensure that the combination of medications you are taking is safe.
  • Avoid grapefruit juice while on this medication.

Macitentan - Dosage and How to Use

How should Macitentan be used?

Macitentan is available as a 10mg tablet, to be taken by mouth once per day. Macitentan can be taken with or without food.

As this medication may cause birth defects, female patients of childbearing age should take precautions by using at least 2 reliable methods of contraception to avoid pregnancy. If you suspect you may be pregnant, inform your Cardiologist as soon as possible.

What should I do if I miss a dose?

If you forget to take a dose, take it as soon as you remember but do not take two doses at once.

What should I do if I overdose?

Macitentan - Handling

How should I handle Macitentan safely?

Macitentan - Storage

How should I store Macitentan?

Keep away from children;#Keep in a cool, dry place, away from direct sunlight;#

How should I dispose of Macitentan safely?

Macitentan - Additional Information

Do not stop taking this medication suddenly without informing your Cardiologist, Nurse and/or Pharmacist as it may make your condition worse.

  • Updated on
  • Article contributed by Department of Pharmacy National Heart Centre Singapore

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