A drug, or pharmaceutical, is a substance used to prevent or cure a disease or ailment or to alleviate its symptoms. In the U.S., some drugs are available over-the-counter while others can be purchased only with a doctor's prescription.

Is a pharmaceutical a drug?

In pharmacology, a drug is a chemical substance, typically of known structure, which, when administered to a living organism, produces a biological effect. A pharmaceutical drug, also called a medication or medicine, is a chemical substance used to treat, cure, prevent, or diagnose a disease or to promote well-being.

What drugs are considered pharmaceutical?

Antibiotics, vaccines, human blood-plasma fractions, and steroid hormones are other important pharmaceuticals manufactured from natural substances. Vitamins, which were formerly obtained from natural sources, are now often made in the laboratory.