Dear Teachers,

1. What's the difference between "medicine" and "drug"?. Could they be used interchangeably?

Thanks a bunch to Teachers,

Heroin is a drug but not a medicine, so no, these terms are not interchangeable.

A drug is a single chemical substance in a medicine that alters the structure or function of some of the body's biological processes. A medicine is drug (or combination of drugs) that is intended to prevent illness, cure decease and pain relievers. Not all drugs are medicines, for example Alcohol and nicotine.