Fosaprepitant 150mg Injection is an antiemetic medication. It blocks the action of a chemical messenger in the brain that may cause nausea and vomiting during treatment with anti-cancer medicines. Uses: Fosaprepitant 150mg Injection is used to prevent nausea and vomiting caused by chemotherapy. Side Effects: Constipation, Fatigue, Diarrhoea, Indigestion, Headache, Decreased appetite, Hiccup, Increased liver enzymes.