What should you pay attention to when taking macitentan?

Macitentan (macitentan) is an endothelin receptor antagonist, mainly used to treat pulmonary arterial hypertension (PAH, WHO group 1). Its role is to delay the progression of the disease, including reducing the risk of death and avoiding the use of Use intravenous or subcutaneous prostaglandins, and improve the patient's clinical symptoms, such as 6 minutes walking distance and PAH related symptoms. In addition, macitentan can reduce the hospitalization rate of PAH patients. The recommended dose is 10 mg taken orally once daily with or without food, but should not be broken in half, crushed or chewed. It should be noted that there is currently no research data on doses higher than 10mg, so excessive dosage is not recommended.

Patients should be particularly aware of the risks of pregnancy while using macitentan. This drug has a clear teratogenic effect on the fetus, so it is strictly prohibited to be used by pregnant women. Women of childbearing age must confirm a negative pregnancy test result before starting treatment, take a pregnancy test once a month during treatment, and take reliable contraceptive measures. Breastfeeding women should also avoid use, as it is not known whether the drug is excreted in breast milk, but animal studies have shown it may have adverse effects on infants. Male patients should be aware that this drug may negatively affect sperm production, thereby affecting fertility.

Liver function monitoring is another important matter while taking macitentan. This drug may cause hepatotoxicity, manifested by elevated transaminases and even liver failure. Liver function needs to be checked before treatment and reviewed regularly during treatment. If the transaminase level exceeds 3 times the upper limit of normal, or is accompanied by symptoms of liver damage such as jaundice, the drug should be discontinued immediately. It is not recommended for patients with moderate hepatic impairment and is contraindicated for patients with severe hepatic impairment. In addition, patients should be alert to the risk of fluid retention, especially those with preexisting left ventricular dysfunction. If symptoms of edema or fluid retention occur, seek medical attention promptly to evaluate the cause and discontinue medication if necessary.

Macitentan may also cause a decrease in hemoglobin, so hemoglobin levels need to be monitored before and during treatment. Its use is not recommended for patients with severe anemia. For patients with pulmonary veno-occlusive disease (PVOD), if symptoms of pulmonary edema occur during medication, the possibility of PVOD should be considered and the medication should be discontinued. Use with caution in elderly patients and patients with renal insufficiency, especially those with severe renal impairment, as the risk of hypotension and anemia may be higher.

In terms of drug interactions, macitentan should be avoided combined withCYP3A4strong inducers (such as rifampicin, carbamazepine) or inhibitors (such as ketoconazole, ritonavir) to avoid affecting the efficacy or increasing the risk of adverse reactions. Although macitentan has little effect on the metabolism of warfarin, sildenafil and other drugs, it still needs to be used in reasonable combination under the guidance of a doctor.

In short, macitentan is an effective drug for the treatment of pulmonary arterial hypertension, but it is necessary to strictly follow the doctor's instructions during the medication, monitor relevant indicators regularly, and pay close attention to possible adverse reactions to ensure the safety and effectiveness of the treatment.

Reference materials:https://www.opsumit.com/