Relapse

In medicine, relapse or recidivism is a recurrence of a past (typically medical) condition. For example, multiple sclerosis and malaria often exhibit peaks of activity and sometimes long periods of dormancy, followed by relapse or recrudescence.

In the context of drug use, relapse or reinstatement of drug-seeking behavior, is a form of spontaneous recovery that involves the recurrence of pathological drug use after a period of abstinence. Relapse is often observed in individuals who have developed a drug addiction or either form of drug dependence.

Substances that may cause addiction or dependence include:

The Drug Enforcement Administration (DEA) has categorized controlled substances into 5 major categories based on the drug’s intended use and potential for addiction and dependence. Drugs with the highest addictive potential are listed in DEA Schedules I and II. Schedule I drugs are those with no accepted medical or therapeutic use whereas Schedule II drugs are those that can be used therapeutically but may lead to severe physical or psychological dependence.

The addictive potential of a drug varies greatly between substances and is based on both the rewarding and reinforcing properties of a drug. Addictive drugs tend to induce euphoria, otherwise known as a drug high.

The three main categories of harm are the physical harm of the drug to the user, the drug’s tendency to cause dependence, and effects of the drug on society.

The first category can be further divided into three parameters of harm: acute physical harm, chronic physical harm, and intravenous harm. Acute harm is defined as the immediate effects associated with use of the given drug such as respiratory depression or myocardial infarction. Chronic harm is the consequence of continued and repeated use such as psychosis or lung disease. Lastly, intravenous harm refers to problems associated with the route of administration such as the spread of blood-borne pathogens like HIV.

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Wikipedia