FRESNO, Calif. (KFSN) -- Years of back pain disappeared in a green flash when Rose Maxey started taking CBD pills.
But the pain returned in the form of shame when she took a drug test for a temp job.
"THC showed up in my urine. Mind you, I am 61 years old. Never flunked a drug test. I don't do drugs. I don't even smoke cigarettes," she says.
There's a fine line between treatment and trouble.
CBD is the compound in cannabis known for its medicinal properties.
THC is the psychoactive component.
Federal law allows CBD derived only from hemp plants, and containing no more than 0.3% THC - far below the 5% or more you'll find in marijuana.
The first reason CBD users can get rolled up in a predicament is a lack of sophistication in urine testing.
"It's possible that with some of the screening tests for THC, they might mistake CBD for THC," says forensic toxicologist Dr. Alan Barbour.
Barbour launched the Valley's first marijuana screening facility.
He says a professional blood test should clear up whether someone has consumed THC.
The second reason CBD users must be wary: the CBD industry is self-regulated.
So what do CBD business owners tell their customers when they want to know if they'll test positive for THC?
"These products are generally not coming from government-sanctioned programs, so their regulations haven't caught up," says Scott John Van Horn of the CBD Center.
Adds Steve Penn of Central Valley CBD Pure, "Read the label, it's on you. And really, that's what this game is. You can't be blaming everybody for something you don't pay attention to, or you don't ask the right questions, or you don't read the bottle."
CBD is legal, but businesses are still operating in a gray area.
The FDA has not reviewed CBD products and hasn't evaluated whether they're safe or effective for treating any disease.
Senate majority leader Mitch McConnell recently pushed the agency to finalize rules for CBD, including certified testing to make sure THC levels are low.
For once, most businesses are excited at the potential for regulation.
"Regulation's good so that we can fall back on something. Unregulated, how can that be good? When people are getting tested, can get in trouble," says Shannon Johnson of Tower Health Foods.
Rose Maxey says regulation or not, she'll keep using CBD because it works.
She'll just cut back if she ever has a drug screening again.
CBD users, beware! You could fail drug tests even if there's no THC in what you're using
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