Schizophrenia. Research on the use of cannabidiol for psychotic symptoms in people with schizophrenia is conflicting. Some early research suggests that taking cannabidiol four times daily for 4 weeks improves psychotic symptoms and might be as effective as the antipsychotic medication amisulpride. However, other early research suggests that taking cannabidiol for 14 days is not beneficial. The conflicting results might be related to the cannabidiol dose used and duration of treatment.
Outside of those four states, consumers must put their trust in the manufacturer. Sometimes that’s warranted, and sometimes it’s not. In 2016 and 2016, the FDA ran tests on several CBD products and found that many of the products had far less CBD than advertised, and in some cases none at all. You can find those test results here for 2015, and here for 2016. (These FDA tests were done as a one-off project. CBD products are not approved by the FDA for the prevention, mitigation, or treatment of any disease or condition.)