Types of drugs:

1. Over the counter drug (OTC): Drugs that are sold directly to a consumer without prescription from healthcare or professionals. Ex: paracetamol, iron tab, vitamin.
2. Prescription drugs: Drugs which cannot be sold to consumer without authorized prescription from healthcare is called prescription drugs. Ex: Sedatives
3. Control drugs: Drugs which can never be dispensed with prescription are called control drugs. Ex: pethidine, heroine, etc. They produce addiction.
4. Experimental drugs: Drugs which are on trial are called experimental drug.
5. Official drug: Drugs which are included in pharmacopoeia.

# Rational uses of drugs/aim of drug used/ benefit of the recipient:

1. Diagnosis of disease: Barium salt for diagnosis of GIT lesions by barium metal X-ray
2. Prevention of disease: Vaccines prevent communicable disease; contraceptives prevent unwanted pregnancy.
3. Control or suppression of disease: Insulin is used for control of diabetes. Anti-hypertensive drugs control hypertension.
4. Treatment of disease: Antibiotic are used for treatment of infection, Antipyretic for pyrexia, Analgesic for pain.

Nomenclature of Drug:

Nomenclature implies assigning proper names to a particular compound so that it’s study, marketing or use may become systematic. Most drugs available in the market have at least three different names:

1. Chemical name
2. Non-proprietary name
3. Proprietary name

1. Chemical name:

• This name is given to a drug in accordance with the rules of chemical nomenclature established by naming conventions like IUPAC (International Union of Pure and Applied Chemistry) or CAS (Chemical Abstract Service)
• Useful to the chemists, scientists or technical personnel as it provides arrangement of atoms and atomic groups in molecules and the chemical constitution of the drug.

2. Non-proprietary name:

• Short name given to a drug that is not subject to proprietary rights.
• This name is easy to speak and sell and often designated to identify a particular drug entity.
• Replaces the chemical name for a pharmaceutical substance. It is also referred as generic name.
• Two classes of non-proprietary names:
  • Approved name
  • Official name

a. Approved name:

• Name given to drug-by-drug nomenclature bodies like United States Adopted Names (USAN) council soon after its introduction.
• Approved name of the drug may or maynot be included in the pharmacopoeia.

b. Official name:

• It is the name approved by the National Pharmacopoeia Commission and is included in the official book Pharmacopoeia.
• Official name may not be approved immediately after introduction of a new drug.

Name stem: Stem is a term used to define the pharmacologically related group to which the drug belongs. Stems are selected by WHO experts and are mostly used as suffix, but in some cases as prefix.

3. Proprietary name:

• Name given to a drug by the pharmaceutical firm which sells the drug, although it may not have manufactured the drug itself.
• Thus, a single drug may be sold under different proprietary names by different firms.
• Clinicians usually prescribe drugs by their proprietary names.