Marijuana's active ingredient is a chemical called THC, which is thought to trigger psychosis in certain individuals. However, research shows that another compound in marijuana called CBD (cannabidiol) may counteract THC's effect, and could even have antipsychotic properties of its own.

In the latest study, published in the journal Neuropsychopharmacology (second LINK HERE - TA note), Dutch and British researchers reviewed more than 66 past studies on CBD and psychosis, and concluded that the compound offers a number of advantages over current drugs.

"Given the high tolerability and superior cost-effectiveness, CBD may prove to be an attractive alternative to current antipsychotic treatment."

The authors point out that CBD, unlike a vast majority of medicines, appears to have no noticeable side effects and no lethal dose. Several lines of evidence, including animal and human studies, also support its effectiveness as an antipsychotic medicine.

One of the most promising studies was published in 2012. The study involved 39 people with schizophrenia, 20 who were given CBD and 19 who were given the antipsychotic drug amisulpride.

At the end of the four-week trial, those who received CBD showed the same levels of improvement as those who received amisulpride. But more importantly, CBD did not cause the hormonal and weight imbalances that amisulpride did.

"The results were amazing," said Daniel Piomelli, Ph.D., a professor of pharmacology at the University of California-Irvine who co-authored the study.

"Not only was (CBD) as effective as standard antipsychotics, but it was also essentially free of the typical side effects seen with antipsychotic drugs."

Unfortunately, despite raising excitement among others in the field, Dr. Piomelli's findings have yet to be followed up. According to PsychCentral, barriers include CBD's relationship to marijuana and the fact that it is a naturally-occurring compound, which makes it harder to patent as a new drug.

The authors of the latest study say that larger trials are necessary in order to bring the medicine to patients.

On the other hand, to get around the patenting issue, they note that identifying the source of CBD's antipsychotic properties "could also lead to the design of new synthetic agents" that mimic its benefits.

The study received funding from the Netherlands Organization for Scientific Research

Source: LeafScience