CBD is on its way to being legal in all 50 states, but enforcement and regulations vary widely by region.

Among the first to legalize recreational cannabis, the state of Washington is now taking a step back. It’s following four others — New York, Maine, North Carolina and Ohio — in a crackdown on CBD products this year. This isn’t necessarily new information, but it was brought to the public’s attention once more when former FDA commissioner Scott Gottlieb discussed the issue on CNBC’s “Squawk Box” earlier this month.

Amid growing concerns about e-cigarette and vaping safety, the conversation turned to CBD. Is it okay to use it when you sleep? What about sprinkling it into a cocktail at a hip, trendy bar?

“There’s demonstrated therapeutic uses of CBD… I suspect we’re going to demonstrate other clinical uses for CBD. But you need to be delivering it in a purified form, in standard doses so you know what you’re getting,” he said.

He criticized many types of commercially available CBD, especially online, that actually contained high concentrations of THC. When a woman recently told Gottlieb she was using CBD products that worked for her dog and relaxed him, Gottlieb wrinkled his nose in confusion.

“That dog was high,” one of the hosts responded.

“Exactly,” Gottlieb said with a laugh. “I didn’t ask if he had the munchies too.”

WOOF: This is what happens when you eat your dog’s CBD treats

Furthermore, he revealed, that $5 CBD add-on that you might see on the menu at brunch, or infused in a latté at your favorite coffee shop, is still a no-go in the eyes of the law. Meanwhile, the industry is expected to grow exponentially — CBD will be worth upwards of $2.6 billion in the next three years.

“You can’t just put it in the food supply,” Gottlieb said. “Right now, all the CBD is illegal that’s being put into food or dietary supplements.”

A new policy update from the Washington State Department of Agriculture clarified the same sentiment.

CBD SNACKS: Check out the restaurants that infused their food on 4/20

“To be clear, CBD is not currently allowed as a food ingredient, under federal and state law,” the Washington State Department of Agriculture said.

But the bans could be temporary, meaning restaurants will simply have to play the waiting game until pending FDA regulations ensure people know what exactly is in their product.

Have comments on this article or questions about cannabis? Ask GreenState or send inquiries and tips to amanda.bartlett@sfchronicle.com