psychiatric disorders
Substance Use Disorders
Physiologic effects of substance use
These substances all directly activate the brain reward system and produce feelings of pleasure. The activation may be so intense that patients intensely crave the substance and neglect normal activities to obtain and use it. These substances also have direct physiologic effects, including Intoxication Withdrawal Substance-induced psychiatric disorders The specific manifestations and treatment of intoxication and withdrawal vary by the substance or substance class and are discussed elsewhere in THE MANUAL. 