Marketing a cannabis product is tricky — and getting even trickier. As states legalize marijuana, they are also adopting their own regulations that can vary widely. 

With recreational marijuana legal in nine states and medical marijuana in 29, the National Association of Cannabis Businesses has proposed advertising rules to guide cannabis marketing across the country.

The medical marijuana guidelines include not making unsubstantiated health claims and specifically saying a product can only be used by authorized patients. The rules take cues from other highly regulated industries like alcohol and tobacco, including not marketing to people under age 21 or depicting excessive consumption of cannabis in advertising.

“As cannabis’s legitimacy increases, it becomes increasingly more important for the industry to be appropriate in the types of claims it’s making,” said Doug Fischer, chief legal officer and head of national standards development at NACB. “The increasing government interest certainly makes it more important to be very conscious of how the industry presents itself.”

NACB’s rules on marketing to underage audiences are also similar to those for alcohol and tobacco. Cannabis advertising cannot use marketing tactics like cartoons, toys, celebrities, or mascots that are commonly employed to pitch to underage audiences.

Digital, TV, radio, and print ads should only be placed where no more than 15% of the audience is under 21. Cannabis websites also need an age-screening component where users must input their date of birth to prove they’re older than 21 to view the website.

Many of these rules can be found in individual state regulations on cannabis, though variations exist among states. For example Connecticut’s underage rule only applies to people under 18, rather than 21, while California’s underage audience rule is less stringent, with the expected underage audience can be up to 30%, rather than 15%.

Some states prohibit advertising of marijuana completely, like Montana, while other states such as Michigan and Minnesota, have no advertising regulations for its medical marijuana.

The rules are up for a public comment until May 25. Fischer expects some changes may be made as cannabis companies and regulators weigh in.

“Because state regulation is so fragmented, there are a lot of approaches in different states,” Fischer said. “It’s important for the industry to express its view on the most effective way to regulate and to drive discussion at state level now and, in the near future, at the federal level. If you can come up with a set of best practices and ensure businesses are adhering to them wherever they operate, then government regulators will know they are legitimate.”