Though CBD is generally well tolerated and considered safe, it may cause adverse reactions in some people.

Side effects noted in studies include (40Trusted Source):

• Diarrhea
• Changes in appetite and weight
• Fatigue

CBD is also known to interact with several medications. Before you start using CBD oil, discuss it with your doctor to ensure your safety and avoid potentially harmful interactions (41Trusted Source).

This is especially important if you take medications or supplements that come with a “grapefruit warning.” Both grapefruit and CBD interfere with cytochromes P450 (CYPs), a group of enzymes that are important to drug metabolism.

One study performed on mice showed that CBD-rich cannabis extracts have the potential to cause liver toxicity. However, some the mice in the study were force-fed extremely large doses of the extract.