The symptoms of “brief psychotic disorder” are similar to those of schizophrenia; however, they last less than 1 month (but at least 1 day). Patients with this disorder can return to their baseline functioning after the disorder has resolved. If this disorder lasts longer than 30 days, then it is diagnosed as schizophreniform disorder or schizophrenia based on the duration of symptoms.
A diagnosis of brief psychotic disorder must rule out depressive or bipolar disorder with psychotic features, as well as psychosis due to the effects of a substance (e.g., a drug of abuse or medication) or another medical condition.
Does substance abuse make Schizophrenia symptoms worse?
Yes. All drugs of abuse (other than tobacco), are associated with poor function in schizophrenia patients. Alcohol abuse increases risk of hospitalization and, in some patients, may increase psychotic symptoms. Studies show that individuals reporting high levels of cannabis use are at a sixfold increased risk of schizophrenia compared with nonusers. The use of amphetamines, cocaine and other illicit drugs have a marked ability to increase psychotic symptoms.