A review on the cannabinoids impacts on psychiatric disorders

Abstract

Psychiatric adverse effects of cannabis are mainly due to psychotic symptoms. In addition, it's one of the most used drugs by patients with severe mental disorders. Cannabis dependence must therefore be treated concurrently with the mental disorder it often coexists with. Cannabis dependence is treated with motivational strategies and cognitive-behavioral techniques. These techniques have proven superior to the techniques used in control groups, despite low adherence to treatment and frequent relapses. Data from clinical trials are scarce for pharmacological interventions. Other useful drugs have been investigated for mental and addictive disorders, often with negative results; on the other hand, there are drugs that specifically act on cannabinoids. The most successful trials have been conducted with cannabinoid antagonists, phytocannabinoid extracts, nabilone and, mainly, dronabinol. Few clinical trials exist regarding the treatment of comorbid mental disorders. A typical antipsychotics for mania, and anticonvulsants for maintenance treatment of bipolar disorder are recommended by observational studies and published case reports in these patients. In animal experiments, the cannabinoid system is suggested as a possible therapeutic target for treating depression and anxiety symptoms in patients with this dual condition. To treat psychosis and dependence, both approaches must be employed. In this population, cognitive-behavioral therapy and motivational strategies have proved effective. Despite little research on cannabis consumption, clinical cases indicate that cannabis abstinence is an important factor in the progression of psychosis and that most clinicians choose atypical antipsychotics for the management of these conditions.

Keywords

• cannabis
• comorbidity
• treatment
• psychosis
• mood disorders
• anxiety