A moss-like plant grown only in a few countries may offer better pain relief than medical marijuana, animal research suggests.

THC (tetrahydrocannabinol) from marijuana is used to treat conditions such as pain, muscle cramps, dizziness and loss of appetite. However, while medical marijuana is increasingly accepted in the United States, it’s illegal in many countries and can cause significant side effects.

Swiss scientists are working with a potential alternative. They say the liverwort plant (Radula perrottetii) contains an anti-inflammatory substance called perrottetinene that’s related to THC. The plant only grows in Japan, New Zealand and Costa Rica.

“This natural substance has a weaker psychoactive effect and, at the same time, is capable of inhibiting inflammatory processes in the brain,” researcher Andrea Chicca said in a University of Bern news release. Chicca is with the university’s Institute of Biochemistry and Molecular Medicine.

Using a synthetic version of the compound on lab animals, the researchers found that perrottetinene reaches the brain easily and activates cannabinoid receptors there. They said it also has a stronger anti-inflammatory effect in the brain than THC.

However, this is still early stage research, the scientists noted, so medical pot won’t have competition anytime soon. And research on animals often doesn’t produce the same results in humans.

The study was published Oct. 24 in the journal Science Advances.

Japanese researchers in the 1990s were the first to identify the psychoactive compound in the liverwort plant. Previously, it was thought that only marijuana produced psychoactive effects, according to background notes with the study.