By Carla K. Johnson and Candice Choi

The Associated Press

With CBD showing up everywhere, U.S. regulators announced Tuesday they are exploring ways the marijuana extract could be used legally in foods, dietary supplements and cosmetics.

The U.S. Food and Drug Administration said it will hold a public hearing May 31 to gather more information on the science, manufacturing and sale of cannabis compounds such as CBD.

In the meantime, it issued more warning letters to companies for making unapproved health claims about CBD products.

Products containing CBD are already in stores and sold online. But the claims are largely unproven and quality control standards don’t exist.

What is CBD?

CBD is one of more than 100 compounds found in marijuana. It’s added to oils, mixed into creams and lotions and sold in candies and liquid drops.

Widely sold, CBD now is going mainstream with major retailers offering salves and balms for the skin. Prices range from $12 to $150 an ounce at high-end shops.

CBD often comes from hemp, which is defined by the U.S. government as having less than 0.3 percent THC, the compound that causes marijuana’s mind-altering effect. CBD doesn’t get people high, although it may be calming. Some CBD products may contain THC, whether or not the label says so.

Is it a miracle cure?

If you believe the hype, CBD treats pain, relieves anxiety and both helps you sleep and keeps you focused.

Most claims are based on studies in rats, mice or in test tubes. Some human research has been done, but in small numbers of people.

One exception: For two rare seizure disorders, the evidence for CBD was strong enough to convince the FDA to approve the drug Epidiolex, which contains a purified form.

The FDA announced Tuesday it has sent warning letters to three companies marketing products with what outgoing Commissioner Scott Gottlieb called “egregious, over-the-line claims” for CBD’s effects on cancer, Alzheimer’s disease, fibromyalgia and drug addiction.

Any side effects?

Scant research means not much is known about side effects either. In epilepsy research, CBD changed the way the body processed other drugs. That suggests CBD could interact with medications in ways we still don’t know about.

The most common side effects of Epidiolex include sleepiness, decreased appetite, diarrhea, increases in liver enzymes, exhaustion, rash and infections. FDA’s Gottlieb noted Tuesday the potential for liver injury and other risks can be handled with medical supervision but less is known about how that would be managed without oversight. And there are questions about overlap if multiple CBD products are used.

Is it legal?

For now, the agency has said CBD is not allowed as an ingredient in food, drinks or dietary supplements. The FDA cited a provision of the law prohibiting food makers from using active drug ingredients or those still undergoing substantial research. But the agency doesn’t have the resources to police all CBD products that are already available, said Marc Scheineson, a former FDA official.

“They’re not going to pull a thousand products from the market,” he said.

The FDA’s authority is over interstate commerce, and local officials have taken differing approaches.

Marijuana itself is illegal under federal law; most states that have legalized it allow marijuana-infused foods and candies, called edibles.

Are CBD labels accurate?

What you buy may contain much less CBD than the label states — or much more. It may include more THC than you want and it may be contaminated with mold or pesticides. Ask to see testing reports.

What’s ahead?

CBD research is planned or underway for cancer, autism, diabetic neuropathy, fibromyalgia, chronic pain, alcoholism with PTSD and psychiatric conditions. Results will take years, but some people aren’t waiting.