People take it for anxiety and inflammation. Arthritis. Insomnia. Pain.

Cannabis vendor Kenneth Oliver says it's frustrating to turn droves of potential customers — many of them looking for medicine — away.

"Because there's only two out of 10 suppliers actually shipping to us, we can't really give them what they need," Oliver said. "A lot of people leave unhappy."

Every second old person is looking for it. - Kenneth Oliver

The owner of the Herbal Centre in St. John's, an independent cannabis store, has gotten his hands on the product only a few times. It sells out almost immediately, he says, with people snapping up boxes at a time.

Cannabidiol, also known as CBD, typically comes in oils, sprays and capsules, and can be absorbed through the mouth or ingested. In Newfoundland and Labrador, two brands have made their way — sparingly and briefly — to shelves: a spray by Aphria and an oil by Canntrust.

Kenneth Oliver, who owns the Herbal Centre, says on some days, every other person walking through the door wants only CBD products. (Malone Mullin/CBC)

CBD is often listed alongside the psychoactively potent THC on cannabis products, but packs less of a punch; in fact, it has no ability to make anyone high on its own.

Yet Oliver says it's one of his most sought-after products, and even started a wait list to make sure the most persistent are first in line when he finally gets another shipment.

"I'd say every second old person out there is looking for it," he said, laughing.

CBD is even marketed to pets: Oliver says he notices his 14-year-old dog stops limping from arthritis when he administers it. (Malone Mullin/CBC)

Oliver says he doesn't hawk CBD as a medical product or dispense advice to customers — by law, he's not allowed to— but the people asking for it have already heard about its apparent wonders, and in some cases, experienced relief themselves.

"I had one guy come in and he had arthritis in his knees, and he said once he started taking the CBD oil, he cancelled his surgery," Oliver said. "He was able to walk again."

Miracle cure, or snake oil?

Few studies on CBD have looked at its effect on anxiety or sleep disorders, but some evidence shows it may lessen seizure frequency in people with epilepsy.

Dr. Alia Norman, a physician at Canabo Medical Clinic in St. John's, says CBD could theoretically be nothing more than a placebo when it's used for pain or stress.

But she suspects otherwise, pointing to a considerable number of her patients who report reduced symptoms after starting a CBD regimen. Some even limited their narcotics use after starting CBD.

Dr. Alia Norman spent years caring for cancer patients, but has recently widened her focus to include any medical issue that might be aided by cannabis. (Malone Mullin/CBC)

"Because it's so biologically active, it seems to benefit people with a wide variety of conditions," she said, noting that people come to her for problems as diverse as back pain, nausea from chemotherapy, and inflammatory bowel disease.

A study in 2010 showed decreased blood flow to brain areas associated with anxiety, while animal models also offer promising results. CBD is still under-researched, Norman said, but added it's increasingly a popular subject.

She counted 187 clinical trials either in progress or planned, pointing to a surge of interest in the various symptoms CBD might alleviate.

Like THC, CBD is believed to affect the endocannabinoid system, which Norman describes as the body's tuning mechanism: we naturally produce cannabinoid-like molecules to regulate hormones, nerve firing and inflammation.

Norman thinks taking CBD oil, if you're healthy, is relatively low-risk, but still says you'll get the best results for any illness if you see a professional. (Malone Mullin/CBC)

THC boosts that system, but does so by locking on to all receptors, instead of disappearing when it's no longer needed like the body's own chemicals do.

CBD, on the other hand, doesn't appear to lock on to these receptors at all. It's believed CBD has some other way to encourage the body's production of endocannabinoids, and has fewer side effects as a result, meaning patients get the medical benefits of cannabis without worrying about impaired driving or a bad trip.

"CBD is seen as natural [with] low side effects," Norman said. "I'm not convinced that 'natural' and 'low side effects' go together — cocaine, for example — but in the case of CBD, they appear to."

Stock will recover, eventually

A spokesperson for the Newfoundland and Labrador Liquor Corporation said they've also had a tough time keeping CBD products in stock. "These sell out very quickly, but we are hoping to have them back soon," the spokesperson said.

The NLC says it's hoping to snag CBD products soon. (CBC)

Oliver maintains a similar sense of optimism. He thinks CBD supply will level out in a few months and he can scrap the wait list.

Norman, meanwhile, also saw her medical supply dry up last fall, when there was a bottleneck effect due to legalization. But it has since returned, and she has no problem obtaining CBD now.

She warns, however, that despite the demand and hype that's causing CBD to fly off the shelves, it doesn't work for everyone: only one in 10 of her patients sees "spectacular" benefits.

Norman also recommends getting doses from a doctor, ensuring underlying conditions, plus other treatments, aren't being ignored.

"Cannabis is not first-line, medically, for anything," she said.

"If people have really serious problems, like cancer, or inflammatory bowel disease, or they're on multiple medications where you can have drug interactions, you're really best seeing somebody who understands those issues."

But for those who still want the convenience of popping into a store — that is, whenever supply reappears — Norman says if customers are healthy, they're likely at lower risk of adverse effects than if they bought a case of beer.

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