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

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

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