Drugs that do not cure a disorder but relieve pain or symptoms related to the condition; for example, use of an antihistamine for allergic symptoms.

Term referring to the administration of drugs by injection.

Drugs that prevent the occurrence of a condition; for example, vaccines prevent the occurrence of specific infectious diseases.  

Drugs that help determine the cause of a particular health problem; for example, injection of antigen serum for allergy testing.

Drugs that provide substances the body needs to maintain health; for example, estrogen replacement therapy for menopausal women and administration of insulin to patients with diabetes.

Drug formulas that are no longer protected by a copyright.

Medications sold without prescription.

Drugs used to treat and cure a disorder; for example, antibiotics cure bacterial infections.

Term that refers to an oral medication that is coated to protect the drug against the digestive enzymes.