The Food and Drug Administration issued a new report Tuesday that warned consumers about potentially risky side effects of consuming CBD. 

The agency also sent warning letters to 15 companies for selling CBD products illegally. The products were sold online and in some vape shops and other stores in cities across the country.

Currently, it is illegal to market CBD by adding it to food or selling it as a dietary supplement. The FDA said it has "limited data" about the safety of the active ingredient derived from the marijuana plant, touted for its alleged health benefits that come without the high. 

But claims of CBD's relaxation and pain-relieving properties have not been officially verified by the FDA. In fact, the popular product could cause harm to users, or could be manufactured in unsafe facilities, according to the organization. 

The FDA says it has approved only one CBD product -- a prescription drug to treat two rare and severe forms of epilepsy.

According to the advisory, taking CBD could cause the following issues: 

  • Liver injury
  • Side effects from interference with other drugs
  • Injuries from increased sedation and drowsiness when taken with alcohol
  • Changes in alertness
  • Gastrointestinal distress
  • Changes in mood

The FDA also said it doesn't have enough research yet to understand CBD's effect on the developing brain, a developing fetus, male reproductive toxicity, and other bodily functions. 

As the organization continues its research, it says it is looking to "explore potential pathways for various types of CBD products to be lawfully marketed." 

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But in the meantime, it remains against federal law to sell CBD products. The administration issued warnings to the following companies for the sale of CBD products and for posting unverified information online: 

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