The reported hypersensitivity reactions occurred during or shortly after infusion of rolapitant IV emulsion, and hospitalization was required in some cases. Rolapitant emulsion contains soybean oil; patients with known allergies to legumes or other related allergens may be at increased risk of developing a hypersensitivity reaction. IV fosaprepitant (Emend), the other parenteral substance P/NK1 inhibitor formulation approved by the FDA, does not contain soybean oil, but has also been associated with serious hypersensitivity reactions.

Patients with a history of hypersensitivity to soybean oil should not be treated with IV rolapitant. Those with known allergies to legumes or other related allergens should be monitored for signs of hypersensitivity during and following infusion of the emulsion. If a serious reaction occurs, use of rolapitant IV emulsion should be permanently discontinued.