Medical marijuana is legal in more than half of US states. As its presence has increased over the last decade, so has research into the different medical applications of cannabis—including topical cannabis for dermatologic treatment.

“This is something in which the public is extremely interested, and researchers have responded accordingly,” says Jeanette Jacknin, MD, FAAD, a board-certified dermatologist based in Encinitas, Calif. “We’ve learned a great deal about the dermatologic applications of cannabis over the past several years, and we’re continually learning more.”

Because cannabis has anti-inflammatory properties, Dr. Jacknin says, there may be potential for topical cannabis to improve conditions, such as acne, psoriasis, and eczema by reducing the inflammation associated with these diseases. Moreover, she says, no negative side effects have been associated with topical cannabis treatment, aside from contact dermatitis, which could occur with any substance applied to the skin.

According to Dr. Jacknin, those who experience a contact dermatitis rash after applying a topical cannabis product are likely reacting to another ingredient in that product, rather than the cannabis itself. To avoid such reactions, she recommends testing a new product on a small area of skin before using it.

As for that other side effect that people may associate with medical marijuana? “Topical cannabis products are not going to get you high,” Dr. Jacknin says. “These formulations contain little or no THC, which gives marijuana its psychoactive properties.”

Before using topical cannabis treatment, Dr. Jacknin says, it’s important to do one’s homework to ensure that the product comes from a reputable source. And since medical marijuana isn’t legal everywhere, she says, those considering topical cannabis treatment should familiarize themselves with the medical marijuana laws in their state and make sure they abide by them.

While most research into the dermatologic applications of cannabis has focused on topical uses, investigations into oral and inhaled use is ongoing, Dr. Jacknin says, and more research into topical cannabis is also needed. “This is an area that has really exploded in recent years,” she says, “and I expect it to grow even more in the years to come.”