<Tr> <Th> MeSH </Th> <Td> D019966 </Td> </Tr> <Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Substance dependence also known as drug dependence is an adaptive state that develops from repeated drug administration, and which results in withdrawal upon cessation of drug use . A drug addiction, a distinct concept from substance dependence, is defined as compulsive, out - of - control drug use, despite negative consequences . An addictive drug is a drug which is both rewarding and reinforcing . ΔFosB, a gene transcription factor, is now known to be a critical component and common factor in the development of virtually all forms of behavioral addiction and drug addictions, but not dependence . </P> <P> Within the framework of the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM - IV), substance dependence is redefined as a drug addiction, and can be diagnosed without the occurrence of a withdrawal syndrome . It is now described accordingly: "When an individual persists in use of alcohol or other drugs despite problems related to use of the substance, substance dependence may be diagnosed . Compulsive and repetitive use may result in tolerance to the effect of the drug and withdrawal symptoms when use is reduced or stopped . This, along with Substance Abuse are considered Substance Use Disorders ." </P>

Individuals who use substances are said to be dependent on the substance when