Common symptoms include: * Sudden changes in behaviour – may engage in secretive or suspicious behaviour * Mood changes – anger towards others, paranoia and little care shown about themselves or their future * Problems with work or school – lack of attendance * Changes in eating and sleeping habits * Changes in friendship groups and poor family relationships * A sudden unexplained change in financial needs – leading to borrowing/stealing money There are many more symptoms such as physical and psychological changes, though this is often dependent on which<unk>  is being used. It is, however, common that people who use<unk> s will experience unpleasant withdrawal symptoms if the drug is taken away from them. It is also reported that others have strong cravings even after they have not used the drug for a long period of time. This is called being "clean". To determine how the brain triggers these cravings, multiple tests have been done on mice. It is also now thought that these cravings can be explained by<unk> s as a subcategory of personality disorders as classified by the DSM-5.
Substance-related disorder
Benzodiazepine use disorder
Substance dependence
Benzodiazepine dependence
Opioid use disorder
Diving disorders
Stimulant use disorder
Cannabis use disorder