A specific cannabis compound, cannabidiol (CBD), can treat schizophrenia as well as antipsychotic drugs, but with far fewer side effects, according to a preliminary clinical trial.
The research team, led by Markus Leweke of the University of Cologne in Germany, studied 39 people with schizophrenia who had been treated for psychotic episodes.Nineteen patients were treated with amisulpride, an antipsychotic drug that is not approved in the United States but is similar to other approved drugs.
The remaining 20 patients were given CBD, a substance found in cannabis that is thought to be responsible for suppressing or reducing anxiety symptoms. Unlike the main ingredient in cannabis, tetrahydrocannabinol (THC), which can trigger psychotic episodes and worsen schizophrenia, CBD has antipsychotic activity, according to previous research in both animals and humans.
Neither patients nor scientists knew which drug each patient was taking. At the end of the four-week trial, both groups showed significant clinical improvements in their schizophrenic symptoms, and there was no difference between those taking CBD and those taking amisulpride.
“The results were amazing,” said Dr. Daniel Piomelli, a professor of pharmacology at the University of California-Irvine and co-author of the study.
“It was not just that CBD was as effective as standard antipsychotics, but that it did not show the typical side effects observed with antipsychotic drugs.”
Antipsychotic drugs can cause catastrophic, and sometimes permanent, movement disorders. They can also reduce the patient’s motivation and pleasure. The new generation of these drugs can also lead to weight gain and increase the risk of diabetes.These side effects are widely known to be a major barrier during treatment.
In the German study, weight gain and mobility problems were observed in patients taking amisulpride rather than CBD. “These exciting findings should give rise to a great deal of research,” said Dr. John Krystal, president of Yale University School of Psychiatry, who did not participate in the study.He notes that CBD not only had fewer side effects, but also appeared to work better on the so-called “negative symptoms” of schizophrenia, which are extremely difficult to treat.
Negative symptoms of schizophrenia include social withdrawal, decreased pleasure, and lack of motivation. However, since current antipsychotic drugs can cause these adverse symptoms, it was not clear whether CBD was better than amisulpride in relieving these symptoms, or whether CBD simply caused fewer side effects. The results show that if CBD is reproduced, it can be at least as effective as current medications for treating schizophrenia, without the serious side effects that make patients reluctant to take medication.
“The real problem with CBD is that it is difficult to develop, for a number of silly reasons,” Piomelli said. Since it comes from Cannabis, there are obvious political issues surrounding its use. Also, its extraction from the plant is expensive. But perhaps the biggest hurdle is that CBD is a natural compound, and therefore cannot be patented, as any new drug is patented.
Thus, although CBD could outperform current production of antipsychotic drugs, pharmaceutical companies are unlikely to develop it. Researchers are working to develop synthetic forms of CBD that will avoid such barriers. “We have something and we hope to move forward in the near future,” Piomelli said. The study was published online in the journal Translational Psychiatry.
Note All articles published here refer to information on all cannabinoids, but in Greece it is not possible to access THC (Δ9-tetrahydrocannabinol), which is not yet legal in our country.