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Definition and classification

Generic Drug Research
Pharmaceutical drugs of the Philippines
Yaba (Ya ba) drug seized by US Customs

A drug is a substance which may have medicinal, intoxicating, performance-enhancing, or other effects when taken or put into a human body or the body of another animal, and is not considered a food or exclusively a food.[1] The distinction between a drug and a food varies between cultures, and distinctions between drugs and foods and between kinds of drugs are enshrined in laws that vary between jurisdictions and aim to restrict or prevent drug use. Even within a jurisdiction, the status of a substance may be uncertain or contested with respect to both whether it is a drug and how it should be classified if at all. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage.[2]

Pharmacological drugs

In pharmacology, a drug is "a chemical substance used in the treatment, cure, prevention, or diagnosis of disease or used to otherwise enhance physical or mental well-being."[3] Drugs may be prescribed for a limited duration, or on a regular basis for chronic disorders.

Recreational drugs

Recreational drug use involves chemical substances that affect the central nervous system, such as opioids or hallucinogens. They may be used for perceived beneficial effects on perception, consciousness, personality, and behavior. Some drugs can cause addiction and/or habituation.

Natural substances and drugs

Many natural substances, such as beer, wine, and psychoactive mushrooms, blur the line between food and recreational drugs, as when ingested they affect the functioning of both mind and body, and some substances normally considered drugs, such as DMT (Dimethyltryptamine), are actually produced by the human body in trace amounts.


The term "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.[4] 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 and medicine

A medication or medicine is a drug taken to cure and/or ameliorate any symptoms of an illness or medical condition, or may be used 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 (OTC) medications, which are available in pharmacies and supermarkets without special restrictions; behind-the-counter (BTC), which are dispensed by a pharmacist without needing a doctor's prescription; and prescription-only medicines (POM), which must be prescribed by a licensed medical professional, usually a physician.[5]

Pharmaceutical drugs and patents

Many drugs are developed 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.[6]


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 being used to treat certain diseases such as attention-deficit hyperactivity disorder, Parkinson's disease, and Alzheimer's disease.[7]

Recreational drug use and regulation

Recreational drug use is the use of psychoactive substances to have fun, for the experience, or to enhance an already positive experience. National laws prohibit the use of many different recreational drugs, and medicinal drugs that have the potential for recreational use are heavily regulated. Many other recreational drugs, on the other hand, are legal, widely culturally accepted, and at most have an age restriction on using and/or purchasing them. These include alcohol, tobacco, betel nut, and caffeine products in the West, and in other localized areas of the world, drugs such as Khat are common.[8]

Drug administration

Drugs, both medicinal and recreational, can be administered in a number of ways. Many drugs can be administered in a variety of ways rather than just one, such as by inhalation, injection, insufflation, orally, rectally, sublingually, topically, or vaginally.[9]

Legal status and ongoing debates

Because of the legal status of many drugs, recreational drug use is controversial, with many governments not recognizing spiritual or other perceived uses for drugs and classifying them under illegal recreational use. The discussion surrounding the legality, regulation, and classification of various drugs is ongoing in many countries, with different approaches being taken to address public health concerns, addiction, and recreational use.[10]

Therapeutic use of previously prohibited substances

In recent years, there has been a growing interest in the potential therapeutic uses of previously prohibited substances, such as the use of cannabis for medicinal purposes, or the study of psychedelics like psilocybin and LSD for the treatment of mental health disorders, including depression, anxiety, and PTSD. This has led to changes in legislation and public perception in some countries and states, allowing for increased research and access to these substances for medical and therapeutic purposes.[11]

Drug addiction and substance abuse

Drug addiction and substance abuse remain significant public health concerns. Many nations invest in prevention, education, and treatment programs to help those struggling with addiction. Treatment approaches can vary, including behavioral therapy, counseling, and medication-assisted therapy (using drugs like methadone or buprenorphine to help manage opioid addiction).[12]

Harm reduction strategies

Additionally, harm reduction strategies have been implemented in some areas to minimize the adverse health effects of drug use. These may include needle exchange programs, supervised injection sites, and access to naloxone, a medication that can reverse opioid overdoses.[13]


  1. "Drug Definition". Merriam-Webster.
  2. "Controlled Substances Act". Drug Enforcement Administration.
  3. "Pharmacology Definition". Merriam-Webster.
  4. "Drug Etymology". Online Etymology Dictionary.
  5. "Drug Applications and Approvals". U.S. Food and Drug Administration.
  6. "Generic Drug Facts". U.S. Food and Drug Administration.
  7. "Nootropics: An Overview". National Center for Biotechnology Information.
  8. "Psychoactive substances". World Health Organization.
  9. "How Drugs are Developed and Approved". U.S. Food and Drug Administration.
  10. "Drug Prevention and Treatment Standards and Norms". United Nations Office on Drugs and Crime.
  11. "Psychedelic Medicine: A Re-emerging Therapeutic Paradigm". National Center for Biotechnology Information.
  12. "Treatment and Recovery Support". Substance Abuse and Mental Health Services Administration.
  13. "Needle Exchange Programs". Centers for Disease Control and Prevention.

See also

Comprehensive list of medications or pharmaceutical drugs used in the United States with their NDC or national drug code, brand name, dosage, forms of administration etc. sorted alphabetically.

External links

The following is the collection of detailed information and links to the National Institute of Health (NIH) comprehensive drug information portal and other reliable sources of information. Select the drug name below to show drug description, drug classification, other common drug names, and information on the reasons why prescribed, how medication should be used, and what possible side effects could occur.

Drug names

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