Cannabis main driver of mania in psychosis

The clinical data on 500 patients presenting with first-episode psychosis showed cannabis use was the main driver of symptoms of mania, but nicotine use, age and gender also contributed.

Excitement, hostility, elevated mood and increased motor activity were all associated with cannabis use.

However, delusions, hallucinations, negative symptoms and daily functioning were not predicted by cannabis use.

Cannabis users who stopped or reduced their drug intake after diagnosis had the greatest improvement in positive and negative symptoms, mania and global functioning compared with those who continued using cannabis.

Psychol Med 2014; 44: 499-506