Adult Dosing
Pulmonary arterial hypertension (PAH, WHO Group I)
- 10 mg PO Daily; Max: 10 mg per day
Pediatric Dosing
- Safety and effectiveness in pediatric patients have not been established
- Use is contraindicated during pregnancy due to serious birth defect risks; this effect has been seen consistently when administered to animals [US Black Box Warning]
- Exclude pregnancy prior to starting therapy, during therapy (obtain monthly pregnancy tests), and 1 month after discontinuation of therapy. Women of child bearing potential must use any one one highly reliable form of contraception to prevent pregnancy during therapy and for 1 month after discontinuation of therapy [US Black Box Warning]
- For all females, the drug is available only through restricted distribution program called the OPSUMIT Risk Evaluation and Mitigation Strategy (REMS) due to potential embryo-fetal toxicity.
- It may be dispensed only to patients who are enrolled in and meet all conditions prescribed by the OPSUMIT REMS program [US Black Box Warning]
- Other endothelin receptor antagonists (ERAs) have been associated with elevated liver aminotransferases, hepatotoxicity and liver failure.
- Liver enzyme tests should be obtained before initiating therapy and should be repeated as clinically needed. Discontinue use of drug if aminotransferase elevations are accompanied by clinical symptoms of hepatotoxicity
- Dose related decreases in hemoglobin and hematocrit have occurred after administration of ERAs. Initiation of treatment is not recommended if severe anemia is present
- Discontinue therapy if signs of pulmonary veno-occlusive disease are observed
- Possibility of decreased sperm counts has been reported; counsel men about potential effects on fertility
Cautions: Use cautiously in
- Hepatotoxicity
- Severe anemia
- Pulmonary veno-occlusive disease
Pregnancy Category:X
Breastfeeding: It is not known whether macitentan is excreted in human milk. Manufacturer advises caution while administering to nursing mothers.
