So, many of CBD's popularized benefits aren't well-proven. But are there any harms in trying CBD-containing products? In a word, yes. While any reported side effects from CBD alone are minor (think dry mouth and dizziness), they can be serious if the CBD products interact with other medications, experts say. Since CBD is metabolized by the same enzyme in the liver that metabolizes many conventional medicines and supplements, the chemical can cause the levels of other drugs in the system to rise; in some cases – like for those taking a drug to prevent their bodies from rejecting a donor organ – to a deadly level, Tishler says.
Most human studies of CBD have been done on people who have seizures, and the FDA recently approved the first CBD-based drug, Epidiolex, for rare forms of epilepsy. Clinical trials for other conditions are promising, but tiny. In one Brazilian study published in 2011 of people with generalized social anxiety disorder, for example, taking a 600-mg dose of CBD (higher than a typical dose from a tincture) lessened discomfort more than a placebo, but only a dozen people were given the pill.
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