Emend (generic: aprepitant) is a prescription medication used to prevent nausea and vomiting caused by certain cancer treatments or surgery in adults.  Emend belongs to a group of drugs called neurokinin 1 (NK1) antagonists, which block a natural substance called neurokinin from causing nausea and vomiting.

This medication comes in capsule and injectable forms. Emend is taken as 3 doses over 3 days.

Common side effects of Emend include constipation, nausea, and tiredness.