From 2015 to July 2019, the FDA issued 48 warning letters to 23 American manufacturers of CBD products for false advertising and illegal interstate marketing of CBD as an unapproved drug to treat diseases, such as cancer, osteoarthritis, symptoms of opioid withdrawal, Alzheimer's disease, and pet disorders. The FDA said that the letters were issued to enforce action against companies that were deceiving consumers by marketing illegal products for which there was insufficient evidence of safety and efficacy to treat diseases. In July 2019, the FDA stated: "Selling unapproved products with unsubstantiated therapeutic claims — such as claims that CBD products can treat serious diseases and conditions — can put patients and consumers at risk by leading them to put off important medical care. Additionally, there are many unanswered questions about the science, safety, effectiveness and quality of unapproved products containing CBD."
In nature, Cannabis ruderalis typically has the lowest levels of THC, Cannabis sativa has a higher level of THC than it has CBD, and Cannabis indica has a higher level of CBD than it has THC. However, since man has been cultivating cannabis (and especially Cannabis sativa) for thousands of years, the effects of artificial selections have led to several different types of cannabis even within the same species, depending on the purpose the cannabis was cultivated for.
In 2013 a CNN program that featured Charlotte's Web cannabis brought increased attention to the use of CBD in the treatment of seizure disorders. Since then, 16 states have passed laws to allow the use of CBD products with a doctor's recommendation (instead of a prescription) for treatment of certain medical conditions. This is in addition to the 30 states that have passed comprehensive medical cannabis laws, which allow for the use of cannabis products with no restrictions on THC content. Of these 30 states, eight have legalized the use and sale of cannabis products without requirement for a doctor's recommendation.
CBD is otherwise most often used for its potential to provide calm and relaxation. On a chemical level, CBD is known to possess powerful antioxidant properties, which may contribute to reducing inflammation and relieving pain. Ongoing research and study are required to fully understand the potential of the cannabinoids therapeutic effects, but CBD may also help to: