What is a Drug
a) A drug is a chemical substance that affects the processes of body and mind.
b) Any chemical compound used or administered to humans and/ or animals in the process of diagnosis, treatment or prevention for relief of pain or sufferings or to control or improve a physiological process or pathological state.
c) A substance used recreationally for its effects on Central Nervous System.
Generic drugs:
The term “generic” has several meanings as regards drugs:
1. The chemical name of a drug.
2. A term referring to the chemical makeup of a drug rather than to the advertised brand name under which the drug is sold.
3. A term referring to any drug marketed under its chemical name without advertising
The use of generic names for these purposes has many advantages, like:
1. Easy recognition of the type of drugs, particularly when many selected drugs exist in that category
(e.g. all Benzodiazepines have a generic name ending with “zepam”).
2. Drugs can be purchased from multiple suppliers giving the advantage of buying at competitive prices.
3. Product substitution is easy where bioavailability presents a problem.
4. Confusion with brand names can be avoided.
Since chemical names are usually long and complicated, the drugs are given a standard, shorter generic name. Manufacturers will usually give drugs brand names to identify that manufacturer’s version of the product. An example of these three names, using a well-known prescription drug is as follows:
Chemical name — 7-chloro-1, 3-dihydro-1- methyl-5-phenyl-2H-1, 4-benzodiazepin-2-one;
Generic name — diazepam
Brand name — Valium.
Since the research and development of the drug molecule has already been done, the cost of the generic drug is usually less.
All drugs considered to be generically equivalent to a brand-name product must meet strict manufacturing requirements. These requirements include tests that assure that the product is bioequivalent to the brand name product.
Classes of drugs:
The two main classes of drugs are:
(1) Non-prescription drugs
(2) Prescription drugs
(1) Non-Prescription
These drugs are commonly called over-the-counter, or OTC drugs, and can be bought without a prescription.
(2) Prescription drugs (or legend drugs)
These are drugs that require a prescription because they are considered to be potentially harmful if not used under the supervision of a licensed health care practitioner. Certain prescription drugs have additional controls placed upon them. These drugs are called controlled (or scheduled) drugs.
Drug classification according to schedules
Controlled Drugs
A controlled (scheduled) drug is one whose use and distribution is tightly controlled because of its abuse potential or risk. The drugs with the highest abuse potential are placed in Schedule I, and those with the lowest abuse potential are in Schedule V. These schedules are commonly shown as C-I, C-II, C-III, C-IV, and C-V. Some examples of drugs in these Schedules are as follows:
Schedule I –
Drugs with a high abuse risk. These drugs have no safe, accepted medical use. Some examples are heroin, marijuana, LSD, PCP, and crack cocaine.
Schedule II –
Drugs with a high abuse risk, but also have safe and accepted medical uses. These drugs can cause severe psychological or physical dependence. It includes certain narcotic, stimulant, and depressant drugs. Some examples are morphine, cocaine, oxycodone.
Schedule III, IV, or V –
Drugs with an abuse risk less than Schedule II. These drugs also have safe and accepted medical uses. Schedule III, IV, or V drugs include those containing smaller amounts of certain narcotic and non-narcotic drugs, anti-anxiety drugs, tranquilizers, sedatives, stimulants and non-narcotic analgesics. Some examples are acetaminophen with codeine.
Other classifications:
Schedule G:
Details of drugs to be labeled with words “Caution – it is dangerous to take this preparation except under medical supervision” e.g., aminopterin, insulin, metformin, promethazine etc.
Schedule H:
Deals with drugs and medicines, which must be sold by retail only when a prescription by a registered medical practitioner is produced e.g., captopril, atenolol, allopurinol, haloperidol, norfloxacin, etc.
Schedule J:
Disease and aliment (by whatever name described), which a drug may not purport to prevent or cure e.g., appendicitis, blindness, blood poisoning, blood pressure (high or low), etc.
Schedule N:
Deals with minimum equipment of a pharmacy and gives direction regarding (a) entrance of a pharmacy; (b) premises; (c) furniture and apparatus; (d) general provisions,
Schedule P:
Defines life period of drugs (shelf life), the period up to which the drug will remain stable under the storage conditions from the date of manufacture;
Schedule W:
List of drugs that are to be marketed under generic name only.
Schedule X:
Gives name of psychotropic drugs, requiring a special license for manufacture and sale e.g. alprazolam, amfepramone, barbital, benzphetamine, clobazam, clonazepam, clorazepate,etc.
