Negative symptoms of schizophrenia include blunted emotions, a decrease in the frequency of speech, a deterioration in the ability to plan, start or continue any activity, and a reduction in the perception of positive emotions or interest. These symptoms can cause severe problems in social interaction and daily life.
The dose-response curve was also observed in healthy volunteers subjected to anxiety induced by the simulation of public speaking test and by public speaking in real settings. In the first situation, volunteers were asked to speak for a few minutes in front of a video camera, while in the second each subject had to speak in front of a group of other research participants. In both situations, treatment with CBD 300 mg was associated with significant decreases in anxiety symptoms, but this effect was not observed with lower or higher doses.
The opposite effects of THC and CBD
Lately, in 2018, at the South London and Maudsley NHS Foundation Trust in London, United Kingdom, a clinical trial was conducted where 33 antipsychotic medication–naive participants at clinical high risk of psychosis and 19 healthy control participants were studied. The scientists used functional magnetic resonance imaging to inspect the effects of CBD on parahippocampal, striatal, and midbrain function – the three brain functions active in schizophrenia. Observing the level of activation in the left parahippocampal brain cortex, the study concluded that a single dose of CBD may partially normalize dysfunction in the medial temporal lobe, striatum, and midbrain in the individuals at clinical high risk of psychosis.
In the other two trials, the results were contradictory. Treatment with a dose of 1000 mg per day significantly reduced positive symptoms , while the other study with 600 mg per day found no significant symptomatic differences between CBD and placebo. It is possible that the explanation for the contradictory results lays in the difference in CBD doses.
The article underlines the connection between cannabis and psychosis as having a centuries-long history, that goes back to 2700 BC, when Shen-nung pen ts’ao ching ( Divine Husbandman’s Materia Medica ) , the world’s oldest pharmacopeia attributed to Chinese emperor Shen-Nung, stated that “. . . ma-fen (the fruit of cannabis), if taken in excess, will produce visions of devils . . . over the long term, it makes one communicate with spirits.”
“Since CBD opposes some of the effects of THC in the brain, it makes sense it could be useful in treating psychotic disorders,” Pierre says. “There’s also some evidence that CBD has properties similar to antipsychotic drugs.”
Epidiolex.com: “Epidiolex: A treatment innovation.”
What the Experts Say
Because of its link to schizophrenia or psychotic episodes, THC is strictly off-limits if you have schizophrenia or if it runs in your family. So it’s crucial to know what you’re getting. That’s not easy, because the market is flooded with products. Many don’t contain what the label claims, and the terms may be confusing.
National Center for Complementary and Integrative Health: “Cannabis (Marijuana) and Cannabinoids: What You Need to Know.”
Find out how the company grows, tests, and processes its CBD products.