HONOLULU » Synthetic marijuana, known on the street as Spice, can cause a lengthy bout of psychosis in some users, according to research presented at the American Psychiatric Association annual meeting.

Doctors at the Naval Medical Center in San Diego reported on 10 patients who were hospitalized for psychosis after using Spice. The synthetic cannabis is also known as K2, Blaze or Red X Dawn. The drug consists of plant material coated with synthetic chemicals meant to produce a high similar to marijuana.

However, symptoms in the 10 patients, who were ages 21 to 25, included auditory and visual hallucinations, paranoid delusions and thoughts of suicide. Most of the patients recovered from the psychosis in five to eight days, but symptoms lasted as long as three months in some people.

Synthetic marijuana has become an issue in the military, in substance-abuse treatment facilities and other settings because it cannot be detected in standard, urine-based drug tests.