A drug is a substance that when put into the body can change the way the body works.
“A drug is defined as any substance (other than a food or device) intended for use in the diagnosis, cure, relief, treatment, or prevention of disease or intended to affect the structure or function of the body.”
(According to U.S. law)
Example :
Oral contraceptives are drugs that affect the function of the body rather than a disease.
CATEGORIES OF DRUGS
By law, drugs are divided into two categories: prescription drugs and nonprescription drugs.
PRESCRIPTION DRUGS—
Those considered safe for use only under medical supervision—may be dispensed only with a prescription from a licensed professional with governmental privileges to prescribe (for example, a physician, dentist, podiatrist, nurse practitioner, physician's assistant, or veterinarian).
NONPRESCRIPTION DRUGS—
Those considered safe for use without medical supervision (such as aspirin)—are sold over the counter.
Dietary supplements (medicinal herbs and nutraceuticals; are products intended to supplement the diet.
These products may contain vitamins, amino acids, minerals, and herbs or other plant-derived material (botanicals).
Because dietary supplements do not require FDA approval prior to marketing, they do not have to meet the same standards as drugs for safety and effectiveness (efficacy).
DRUG NAMES
Some knowledge of drug names can help in understanding drug product labels.
Every drug has at least three names—a chemical name, a generic (nonproprietary or official) name, and a trade (proprietary or brand) name.
The chemical name describes the atomic or molecular structure of the drug. This name is usually too complex and cumbersome for general use.
So an official body assigns a generic name to a drug. The generic names for drugs of a particular type (class) usually have the same ending.
Example : The names of all beta-blockers, which are used to treat such disorders as high blood pressure, end in "lol."
The trade name is chosen by the pharmaceutical company that manufactures or distributes the drug.
Patented drugs are usually sold under a trade name. Generic versions of trade-name drugs—manufactured after expiration of the pharmaceutical company's patent—may be sold under the generic name (for example, ibuprofen) or under the manufacturer's own trade name (for example, Advil).
DRUG GROUPS
Understanding what group a drug belongs to is also useful.
Broadly, drugs are classified by
THERAPEUTIC GROUP—That is, by what disorder or symptom they are used to treat.
Example :
§ AntiHypertensives : Drugs used to treat high blood pressure.
§ Antiemetics : Drugs used to treat nausea.
Within each therapeutic group, drugs are categorized by classes.
Some Classes are based on how the drugs work in the body to produce their effect.
Example :
§ Diuretics
§ Calcium channel blockers
§ Beta-blockers
§ Angiotensin-converting enzyme (ACE) inhibitors
These drugs are all classes of AntiHypertensives that work differently.
A "soft" drug is less addictive and considered less harmful to the body and to society as a whole.
A "hard" drug is harshly addictive and considered much more harmful to the body and society in general.
Psychoactive drugs are drugs that change your feelings, your perceptions and/or your behavior.
Psychoactive drugs bring about a chemical reaction in the brain causing feelings, thoughts and behavior to be affected.
A legal drug is a drug that can be obtained either by prescription or over the counter and used in the prescribed and appropriate.
An illegal drug is a drug that is not approved by law for use in this country.
LICIT DRUG USE
§ Licit drug use means that a drug is used legally.
Legal use of drugs includes:
Ø Medicines used for illness
Ø Few other legal drugs (alcohol, tobacco and caffeine)
§ Licit use of drugs includes:
Ø Over-the-counter drugs used as directed
Ø Prescription medicines used by intended person for prescribed usage
ILLICIT DRUG USE
§ Illicit drug use occurs when drugs are used in an illegal manner. (i.e. heroin)
§ Illicit drug use includes:
o Using a drug for an improper purpose (sleeping pills to get high or pain pills for relaxation or sleep)
o Using a product or substance not intended to be a drug in a way which produces a drug-like state (glues, petrol)