5-Hydroxitryptamine3 antagonists are one of the mainstays of antiemetic treatment and they are administered either intravenously or orally. Nevertheless sometimes neither administration route is feasible, such as in patients unable to admit oral intake managed in an outpatient setting. Our objective is to evaluate the bioavailability of subcutaneous palonosetron.Patients receiving platinum-based chemotherapy will be randomized to receive palonosetron 3 mg either subcutaneously or intravenously in a crossover manner during two cycles. Blood and urine samples will be collected after each cycle. Pharmacokinetics of subcutaneous and IV palonosetron will be prospectively compared.