A drug is any substance (other than food that provides nutritional
support) that, when inhaled, injected, smoked, consumed, absorbed via
a patch on the skin, or dissolved under the tongue causes a temporary
physiological (and often psychological) change in the body.
In pharmacology, a pharmaceutical drug, also called a medication or
medicine, is a chemical substance used to treat, cure, prevent, or
diagnose 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
Pharmaceutical drugs are often classified into drug classes—groups
of related drugs that have similar chemical structures, the same
mechanism 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
Psychoactive drugs are chemical substances that affect the function of
the central nervous system, altering perception, mood or
consciousness. They include alcohol, a depressant (and a stimulant
in small quantities), and the stimulants nicotine and caffeine. These
three are the most widely consumed psychoactive drugs worldwide
and are also considered 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.
3 Spiritual and religious use
4 Smart drugs and designer drugs
Recreational drug use
6 Administration of drugs
7 Control of drugs
8 See also
10 Further reading
11 External links
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.
Nexium is a proton-pump inhibitor. It is used to reduce the production
of stomach acid.
Pharmaceutical drug and
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 as
preventive 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
pharmacies and 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 a physician.
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 called
generic 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
Main article: Entheogen
An Amazonian shaman
San Pedro, a psychoactive cactus
Some religions, particularly ethnic religions are based completely on
the use of certain drugs, known as entheogens, which are mostly
hallucinogens,—psychedelics, dissociatives, or deliriants. Some
drugs used as entheogens include kava which can act as a stimulant, a
sedative, a euphoriant and an anesthetic. The roots of the kava plant
are used to produce a drink which is consumed throughout the cultures
of the Pacific Ocean.
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
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
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 dreams during the
initiation process of shamans, classifying it a naturally occurring
oneirogen similar to the more well-known dream herb Calea
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 
Rastafari use marijuana (ganja) as a sacrament in
their religious ceremonies.
Psychedelic mushrooms (psilocybin mushrooms), commonly called magic
mushrooms or shrooms have also long been used as entheogens.
Smart drugs and designer drugs
Nootropic and Designer drug
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 are produced. An early example of
what today would be labelled a 'designer drug' was LSD, which was
synthesised from ergot. Other examples 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
Cannabis is a commonly used recreational drug.
Recreational drug use
Further information: Prohibition of drugs
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
consciousness through alteration of the central nervous system in
order to create positive emotions and feelings. The hallucinogen LSD
is a psychoactive drug commonly used as a recreational drug.
Some national laws prohibit the use of different recreational drugs;
and medicinal drugs that have the potential for recreational use are
often heavily regulated. However, there are many recreational drugs
that are legal in many jurisdictions and widely culturally accepted.
Cannabis is the most commonly consumed controlled recreational drug in
the world (as of 2012). Its use in many countries is illegal but
is legally used in several countries usually with the proviso that it
can only be used for personal use. 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.
There are a number of legal intoxicants commonly called legal highs
that are used recreationally. The most widely used of these is
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)
Injection 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
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.
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.
Controlled Substances Act
Inverse benefit law
List of drugs
List of pharmaceutical companies
List of psychoactive plants
List of Schedule I drugs (US)
Specialty drugs (United States)
United Nations Office on Drugs and Crime
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Wikimedia Commons has media related to Drugs.
Pharmacology: major drug groups
Proton pump inhibitors
Blood and blood
forming organs (B)
Calcium channel blockers
Angiotensin II receptor antagonists
Bile acid sequestrants
Thyroid hormones/Antithyroid agents
infestations (J, P, QI)
Antimicrobials: Antibacterials (Antimycobacterials)
and joints (M)
nervous system (N)
Sensory organs (S)
Other ATC (V)
Recreational drug use
nail polish remover
Psilocybin / Psilocin
Atropine and Scopolamine
Legal history of cannabis in the United States
Legality of cannabis
Marijuana Policy Project
Cannabis and religion
Counterculture of the 1960s
Party and play
Poly drug use
Religion and drugs
Sex and drugs
Coca production in Colombia
Opium production in Afghanistan
Rolling meth lab
Illegal drug trade
Date rape drug
Effects of cannabis
Opioid replacement therapy
Fetal alcohol spectrum disorder
Long-term effects of cannabis
of tobacco or other substances
1961 Narcotic Drugs
1971 Psychotropic Substances
Council of the European Union decisions on designer drugs
Drug Policy Alliance
Law Enforcement Action Partnership
Students for Sensible
Drug Policy Foundation
Just Say No
Office of National
Drug Control Policy
School district drug policies
Arguments for and against drug prohibition
Capital punishment for drug trafficking
Politics of drug abuse
War on Drugs
Anabolic steroid legality
Psilocybin mushrooms legality
Amino acids and
Amino acids and related: GABA receptor modulators
GABAA receptor positive modulators
GABA metabolism and transport modulators
GHB receptor modulators
Glutamate metabolism and transport modulators
Glycine receptor modulators
Ionotropic glutamate receptor modulators
Metabotropic glutamate receptor modulators
Monoamines: Adrenergic receptor modulators
Dopamine receptor modulators
Histamine receptor modulators
Melatonin receptor modulators
Monoamine metabolism modulators
Monoamine releasing agents
Monoamine reuptake inhibitors
Serotonin receptor modulators
Acetylcholine: Acetylcholine metabolism and transport modulators
Muscarinic acetylcholine receptor modulators
Nicotinic acetylcholine receptor modulators
Others: Imidazoline receptor modulators
Purine receptor modulators
Sigma receptor modulators
Thyroid hormone receptor modulators
Cannabinoid receptor modulators
Leukotriene signaling modulators
Prostanoid signaling modulators
Phospholipids: Lysophospholipid signaling modulators
PAF receptor modulators
Steroids: Androgen receptor modulators
Estrogen receptor modulators
Glucocorticoid receptor modulators
Mineralocorticoid receptor modulators
Progesterone receptor modulators
Steroid metabolism modulators
Other nuclear receptors: Nuclear receptor modulators
Retinoid receptor modulators
Vitamin D receptor modulators
Xenobiotic-sensing receptor modulators
General: Signaling peptide/protein receptor modulators
Peptides: Angiotensin receptor modulators
GH/IGF-1 axis signaling modulators
GnRH and gonadotropin receptor modulators
Melanocortin receptor modulators
Neurokinin receptor modulators
Opioid receptor modulators
Oxytocin and vasopressin receptor modulators
Cytokines: Cytokine receptor modulators
Chemokine receptor modulators
Interleukin receptor modulators
TNF receptor superfamily modulators
Growth factors: Growth factor receptor modulators
TGFβ receptor superfamily modulators
Enzymes: Cytochrome P450 modulators
Histone deacetylase inhibitors
Ion channels: Ion channel modulators
TRP channel modulators
Transporters: Symporter inhibitors
Others: Nitric oxide signaling modulators