Drug usage

Drugs can be used in many different ways, as detailed below.

Medication
People can use drugs to relieve pain or discomfort or to cure or prevent disease. However, not all medications are drugs.

Recreational drug use
Recreational drug use is the use of psychoactive drugs for recreational purposes rather than for work, medical or spiritual purposes, although the distinction is not always clear. At least one psychopharmacologist who has studied this field refers to it as the 'Fourth Drive,' arguing that the human instinct to seek mind-altering substances has so much force and persistence that it functions like the human drives for hunger, thirst and shelter.

Responsible drug use
The concept of responsible drug use is that a person can use recreational drugs with reduced or eliminated risk of negatively affecting other parts of one's life or other people's lives. Advocates of this idea point to the many well-known artists and intellectuals who have used drugs, experimentally or otherwise, with few detrimental effects on their lives. Critics argue that the drugs are escapist--and dangerous, unpredictable and sometimes addictive; thus predicating the idea of a responsible use of drugs as an idea, ultimately disputable upon debate.

Gateway drug theory
The gateway drug theory is the hypothesis that the use of soft drugs leads to a higher, future risk of hard drug use and crime. The term is also used to describe introductory experiences to addictive substances. Some believe  tobacco, alcohol, and marijuana are gateway drugs.

Some research suggests that serious drug abusers adopt a typical drug use sequence with use of other drugs initiated before marijuana or alcohol. There are many pharmacological similarities between various drugs of abuse. Individual social histories show that "hard" drug users do progress from one drug to another, but the reasons are not clear enough to generalise a gateway.

Drug addiction
Drug addiction is a condition characterized by compulsive drug intake, craving and seeking, despite what the majority of society may perceive as the negative consequences associated with drug use.

Drug abuse
Drug abuse has a wide range of definitions related to taking a psychoactive drug or performance enhancing drug for a non-therapeutic or non-medical effect. Some of the most commonly abused drugs include alcohol, tobacco, amphetamines, barbiturates, benzodiazepines, cocaine, and opiates, opioids, and their derivatives which typically have opioid agonist actions though some don't (e.g. morphine and it's derivatives like heroin (3,6-diacetylmorphine), codeine, dextromethorphan an NMDA antagonist opioid with no opioid activity.) Use of these drugs may lead to criminal penalty in addition to possible physical, social, and psychological harm, both strongly depending on local jurisdiction. Although there is criticism on making drug use illegal and throwing non-violent drug offenders in jail. on Other definitions of drug abuse fall into four main categories: public health definitions, mass communication and vernacular usage, medical definitions, and political and criminal justice definitions.