Cannabinol is a popular ingredient in over-the-counter sleep products, marketed as a gentle, plant-derived way to unwind at the end of the day. But new research done at the University of Connecticut suggests consumers should use it with caution.

Repeated exposure to cannabinol, also known as CBN, can produce signs of physical dependence in mice, UConn researchers report in the November issue of the journal Drug and Alcohol Dependence.

“CBN is everywhere right now. Gummies, tinctures, capsules, and it’s marketed as a safe, herbal sleep supplement,” says Steven Kinsey, professor in UConn’s Elisabeth DeLuca School of Nursing. “Our findings suggest consumers should be aware repeated use may carry risks.”

Like THC (tetrahydrocannabinol) and CBD (cannabidiol), CBN occurs naturally in the cannabis plant. It is often described as less psychoactive than THC. But Kinsey and his colleagues found that CBN activates similar biological pathways as THC and produces hallmark features of drug dependence.

For example, mice given CBN twice daily for three days became tolerant to the drug’s effects, showing the drug had less effect after repeated use. They also showed signs of withdrawal when the drug was taken away, twitching their heads and fluttering their paws in much the way humans’ hands might shake. And mice trained to respond in a certain way to the high from THC respond in the same way to CBN, telling the researchers that CBN “feels like” THC, at least from a mouse’s point of view.

These findings indicate that although CBN is milder than THC, it engages some of the same receptor systems involved in cannabis dependence.

The lead author of the study, Olivia Vanegas ’26 Ph.D., notes “The marketing of minor cannabinoids is pretty wild right now. There are so many therapeutic claims about these drugs, but we really don’t know much about their potential risks, especially with repeated use.”

CBN’s popularity as a sleep aid has soared, but there is very little known about the quality of the sleep induced, or whether CBN taken repeatedly at those doses is addictive. There have been repeated examples over the last century of drugs that were initially marketed as sleep aids but later found to be dangerously habit forming.

The researchers also found that CBN has anti-inflammatory effects, and at lower doses that are not psychoactive.  CBN weakened the body’s defense system during a simulated bacterial challenge, similar to how getting a cut on your foot can make it easier for germs to get in and cause an infection. But more research needs to be done to ascertain the best and safest uses of CBN. As Kinsey points out, this study was done in mice, and more research is needed to determine how CBN affects people, particularly at high doses or over the long term.

“CBN may still have therapeutic value,” he says. “But until we know more about dosing and long-term effects, the message for consumers is simple: buyer beware.”