Antiemetics are drugs used to relieve symptoms of nausea and vomiting. Several medications from different drug classes are used for this purpose, including antidiarrheals, antihistamines, sedatives, dopamine antagonists, serotonin 5-HT₃ receptor antagonists and corticosteroids.

Antiemetics are available in tablet, capsule, syrup, suppository (inserted into the body through a cavity) and injection form.

Different antiemetics work in varying ways, and their effectiveness depends on both the patient who is taking the medicine and the condition that is causing the nausea and vomiting. For example, some antiemetics work better for treating symptoms caused by the flu, whereas others are more adept at treating discomfort associated with motion sickness.

Side effects associated with antiemetic use include darkish tongue or grayish-black stools, drowsiness, fatigue, insomnia and dry mouth among others.

Patients should not take antiemetics without first consulting a physician. Other drugs or certain medical conditions can impact how a patient responds to antiemetic use. Antiemetics should not be used by children, the elderly or women who are pregnant, thinking of becoming pregnant or breastfeeding unless use is approved by a physician.