DRUG

A drug      is any substance other than food, that 

when inhaled, injected, smoked, consumed, absorbed via a patch on the skin or dissolved under the 

tongue causes a physiological change in the body.

In pharmacology, a pharmaceutical drug, also called a medication or medicine, is a chemical 

substance 

used to treat, cure, prevent, ordiagnose a disease or to promote well-being. Traditionally drugs were

 obtained through extraction from medicinal plants, but more recently also by organic 

synthesis.Pharmaceutical drugs may be used for a limited duration, or on a regular basis for chronic 

disorders.

Pharmaceutical drugs are often classified into drug classes—groups of related drugs that have 

similar chemical structures, the samemechanism of action (binding to the same biological target), a 

related mode of action, and that are used to treat the same disease.^{[verification needed]}  The Anatomical 

Therapeutic Chemical Classification System (ATC), the most widely used drug classification system

, assigns drugs a unique ATC code, which is an alphanumeric code that assigns it to specific drug 

classes within the ATC system. Another major classification system is the Biopharmaceutics 

Classification System. This classifies drugs according to their solubility and permeability 

or absorption properties.

Psychoactive drugs are chemical substances that affect the function of the central nervous system, 

altering perception, mood orconsciousness.They include alcohol, a depressant, and 

the stimulants nicotine and caffeine. These three are the most widely consumed psychoactive drugs 

worldwide and are also considered as recreational drugs since they are used for pleasure rather than

medicinal purposes. Other recreational drugs include hallucinogens, opiates and amphetamines and 

some of these are also used in spiritual or religious settings. Some drugs can cause addiction and all 

drugs can have side effects. Excessive use of stimulants can promote stimulant psychosis. Many

 recreational drugs are illicit and international treaties such as the Single Convention on Narcotic 

Drugs exist for the purpose of their prohibition.

Etymology

In English, the noun "drug" is thought to originate from Old French "drogue", possibly deriving later into 

"droge-vate" from Middle Dutch meaning "dry barrels", referring to medicinal plants preserved in 

them.The transitive verb "to drug" (meaning intentionally administer a substance to someone, often 

without their knowledge) arose later and invokes the psychoactive rather than medicinal properties of a

 substance.

Medication

A medication or medicine is a drug taken to cure or ameliorate any symptoms of an illness or medical 

condition. The use may also be aspreventive medicine that has future benefits but does not treat any 

existing or pre-existing diseases or symptoms.Dispensing of medication is often regulated 

by governments into three categories—over-the-counter medications, which are available 

in pharmaciesand supermarkets without special restrictions; behind-the-counter medicines, which are

 dispensed by a pharmacist without needing a doctor's prescription, and prescription only medicines, 

which must be prescribed by a licensed medical professional, usually aphysician.

In the United Kingdom, behind-the-counter medicines are called pharmacy medicines which can only 

be sold in registered pharmacies, by or under the supervision of a pharmacist. These medications are

designated by the letter P on the label. The range of medicines available without a prescription varies 

from country to country. Medications are typically produced by pharmaceutical companies and are 

often patented to give the developer exclusive rights to produce them. Those that are not patented (or 

with expired patents) are calledgeneric drugs since they can be produced by other companies without 

restrictions or licenses from the patent holder.

Pharmaceutical drugs are usually categorised into drug classes. A group of drugs will share a 

similar chemical structure, or have the same mechanism of action, the same related mode of action or

 target the same illness or related illnesses.The Anatomical Therapeutic Chemical Classification 

System (ATC), the most widely used drug classification system, assigns drugs a unique ATC code, 

which is an alphanumeric code that assigns it to specific drug classes within the ATC system. Another 

major classification system is the Biopharmaceutics Classification System. This groups drugs 

according 

to their solubility and permeability or absorption properties.

Spiritual and religious use

Some religions, particularly ethnic religions are based completely on the use of certain drugs, known 

as entheogens, which are mostly hallucinogens, being either psychedelics or deliriants. Some drugs 

used are stimulants and sedatives.^{[citation needed]}

Some shamans from different cultures use entheogens, defined as "generating the divine within" to 

achieve religious ecstasy. Amazonian shamans use ayahuasca (yagé) a hallucinogenic brew for this 

purpose. Mazatec shamans have a long and continuous tradition of religious use of Salvia 

divinorum a psychoactive plant. Its use is to facilitate visionary states of consciousness during spiritual

 healing sessions.

Silene undulata is regarded by the Xhosa people as a sacred plant and used as an entheogen. Its root 

is traditionally used to induce vivid (and according to the Xhosa, prophetic) lucid dreamsduring the 

initiation process of shamans, classifying it a naturally occurring oneirogen similar to the more well-

known dream herb Calea ternifolia.

Peyote a small spineless cactus has been a major source of psychedelic mescaline and has probably 

been used by Native Americans for at least five thousand years. Most mescaline is now obtained from 

a few species of columnar cacti in particular from San Pedro and not from the vulnerable peyote.

The entheogenic use of cannabis has also been widely practised  for 

centuries. Rastafari use marijuana (ganja) as a sacrament in their religious ceremonies.

Smart drugs and Designer drugs

Nootropics, also commonly referred to as "smart drugs", are drugs that are claimed to improve human 

cognitive abilities. Nootropics are used to improve memory, concentration, thought, mood, learning, 

and many other things. Some nootropics are now beginning to be used to treat certain diseases such 

as attention-deficit hyperactivity disorder, Parkinson's disease, and Alzheimer's disease. They are also 

commonly used to regain brain function lost during aging.

Other drugs known as designer drugs produced, include analogs of performance-enhancing 

drugs such as designer steroids taken to improve physical capabilities and these 

are sometimes used (legally or not) for this purpose, often by professional athletes. Other designer 

drugs mimic the effects of psychoactive drugs. Since the late 1990s there has been the identification of 

many of these synthesised drugs. In Japan and the United Kingdom this has spurred the addition of 

many designer drugs into a newer class of controlled substances known as a temporary class drug.

Synthetic cannabinoids have been produced for a longer period of time and are used in the designer 

drug synthetic cannabis.

Recreational drug use

Recreational drug use is the use of a drug (legal, controlled, or illegal) with the primary intention 

of altering the state of consciousnessthrough alteration of the central nervous system in order to create

 positive emotions and feelings. Some national laws prohibit the use of different recreational drugs, and 

medicinal drugs that have the potential for recreational use are often heavily regulated. On the other

 hand, there are many recreational drugs that are legal in many jurisdictions and widely culturally 

accepted.^{[citation needed]} Cannabis is a psychoactive drug and is the most commonly consumed drug in 

the world (as of 2012). It can be used in the leaf form of marijuana(grass), or in the resin form 

of hashish. Marijuana is a more mild form of cannabis than hashish.

There may be an age restriction on the consumption and purchase of legal recreational drugs. Some 

recreational drugs that are legal and accepted in many places include alcohol, tobacco, betel nut, 

and caffeine products, and in some areas of the world the legal use of drugs such as khat is 

common.^[31]

There are a number of legal intoxicants commonly called legal highs that are used recreationally. The 

most widely used of these is alcohol.

Administration of drugs

All drugs, can be administered via a number of routes, and many can be administered by more than one.

• Bolus is the administration of a medication, drug or other compound that is given to raise its concentration in blood to an effective level. The administration can be given intravenously, by intramuscular, intrathecal or subcutaneous injection.
• Inhaled, (breathed into the lungs), as an aerosol or dry powder. (This includes smoking a substance)
• Injected as a solution, suspension or emulsion either: intramuscular, intravenous,intraperitoneal, intraosseous.
• Insufflation, or snorted into the nose

• Orally, as a liquid or solid, that is absorbed through the intestines.
• Rectally as a suppository, that is absorbed by the rectum or colon.
• Sublingually, diffusing into the blood through tissues under the tongue.
• Topically, usually as a cream or ointment. A drug administered in this manner may be given to act locally or systemically.
• Vaginally as a pessary, primarily to treat vaginal infections.

Control of drugs

There are numerous governmental offices in many countries that deal with the control and oversee of 

drug manufacture and use, and the implementation of various drug laws. The Single Convention on 

Narcotic Drugs is an international treaty brought about in 1961 to prohibit the use of narcotics save for 

those used in medical research and treatment. In 1971 a second treaty the Convention on 

Psychotropic Substances had to be introduced to deal with newer recreational psychoactive and 

psychedelic drugs.

The legal status of Salvia divinorum varies in many countries and even in states within the United 

States. Where it is legislated against the degree of prohibition also varies.

The Food and Drug Administration (FDA) in the United States is a federal agency responsible for 

protecting and promoting public health through the regulation and supervision of food safety, tobacco 

products, dietary supplements, prescription and over-the-

counter medications, vaccines, biopharmaceuticals, blood transfusions, medical 

devices,electromagnetic radiation emitting devices, cosmetics, animal foods and veterinary drugs.