What is an antiemetic?

• A. A drug that prevents or stops vomiting
• B. A drug that neutralizes stomach acid
• C. A drug that breaks up mucus and promotes coughing
• D. A drug that reduces fever

Answer: (A)

An antiemetic is a drug that prevents or stops vomiting. It works by blocking or dampening the signals that trigger the vomiting reflex, which is controlled by the brain’s vomiting center and influenced by signals from the stomach, inner ear, and other parts of the body. Different antiemetics target different pathways, such as serotonin receptors, histamine receptors, acetylcholine receptors, or dopamine signals, which helps prevent nausea and vomiting from various causes like motion sickness, pregnancy-related nausea, chemotherapy, or after surgery.

The other options describe medicines with different purposes: something that neutralizes stomach acid helps reduce acidity in the stomach; something that breaks up mucus and promotes coughing is an expectorant; something that reduces fever is an antipyretic. None of these prevent vomiting, which is why they are not antiemetics.