By the time you feel any annoying itch or prick of pain, CB1 and CB2 receptors on your skin cells have already fired off signals to help dampen those unpleasant vibes. These receptors — part of the body’s endocannabinoid system — spend their workdays responding to chemical messages that help our skin nurture a healthy balance. CBD cream bypasses the CB1 and CB2 receptors and heads straight for a neurotransmitter middleman that blocks signals for pain and itch by working through agents called anandamide and 2-AG.
Pain is a big driver behind opioid addiction. Many people who began treating chronic pain with prescription opioids have switched to heroin when other drugs became difficult to get. A lot of people have died as a result, says Yasmin Hurd , an addiction specialist at the Icahn School of Medicine at Mount Sinai in New York. “We have so many people in our society now experimenting with CBD to manage pain,” she says. “They are going to their clinicians and asking them for CBD.”
Sidestepping the CB1 and CB2 receptors means that CBD can mute pain without the high sensation delivered by THC. Not only does CBD have very little interest in switching on CB1, cannabidiol can actually mute any signals sent to that receptor. Researchers looking for safer pain treatments want to take advantage of this action because it means that CBD won’t spark addiction.
CBD is one of the hundreds of biologically active ingredients produced in Cannabis sativa plants. Unlike THC, its psychoactive cousin that makes people feel high, CBD can ease pain without the euphoria or fear of addiction. The cannabinoid has similar effects whether absorbed through the skin or ingested by mouth.
Consumers aren’t waiting for clinical trials. But they need to remember, says Hurd, that slathering on creams can be risky, considering how the skin absorbs everything. Even topical CBD can react with oral medications.
Topical CBD creams can treat pain, discomfort and inflammation. Here’s what science knows about how they work.
Hurd suggests telling your doctor if you are using CBD creams because what’s absorbed into your skin will get into your bloodstream. “These are sometimes things people don’t appreciate when they are putting cream ‘only on my knee,’” says Hurd. “We also have a lot of seniors using CBD creams for arthritic pain and we need to know sooner rather than later whether this chemical cream used by so many people can indeed be effective.”
Researchers have confirmed that CBD works against pain and inflammation , and they’re still finding new ways that it works in the body . They're also working to nail down the proper dose of topical CBD needed for pain relief. For example, the dose that brings relief to achy joints may be insufficient to effectively treat nerve damage in feet. While rubbing topical CBD onto the skin seems to work, researchers still need to figure out how much skin coverage is most effective. Some skin creams also contain menthols, which carry their own pain relief and anti-inflammatory properties, possibly masking any effect from the CBD itself.
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That said, CBD is thought to be a safe and effective option for certain conditions. Below, we sort through the confusion by answering some of the most common questions about CBD.
The safest way to take CBD is orally, as a tablet, chewable, or tincture (a concentrated liquid typically administered with a dropper). Steer clear of any illegally sold synthetic CBD products, sometimes called “spice” or “bath salts.” These products have induced psychotic reactions in some people and pose a major health risk.
Evidence regarding CBD is still building. Now that some states have legalized recreational and medical use of marijuana products, including CBD, scientists are finding it easier to conduct research. More will be known in the next 5 to 10 years, including whether there are yet undiscovered problems associated with long-term use.
CBD and other medications: Proceed with caution
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If you are interested in trying a CBD product, it’s best to seek one through a dispensary, which is an establishment legally licensed to sell marijuana, if they are available in your state. Dispensary products must be labeled so you can see exactly how much CBD is in the product and whether it also contains THC. A small amount of THC in a CBD product isn’t typically problematic. But larger amounts could cause a “high” and may present a risk if you are going to drive.
Also, keep in mind that CBD products aren’t standardized and will vary. It helps to keep a journal recording what type of CBD product you took, how much, and your response to it. This will help you track what works and what doesn’t for your condition.
Is marijuana-derived CBD legal?
When it comes to CBD products, the FDA is still trying to get its arms around the issue. The agency is just starting the process of hashing out some rules regarding CBD sales. Officials recently formed a working group to create guidelines that could allow companies to legally market CBD products. Currently, CBD products are considered supplements, which aren’t FDA-regulated, and it is illegal for companies to make health or therapeutic claims about the products in their marketing. In announcing its effort to set CBD marketing rules, the FDA also signaled that it is cracking down on CBD companies that are using “egregious and unfounded claims” to market their products to “vulnerable populations.”
Testing also shows that many products don’t contain what’s claimed on the label. For example, they may have less CBD than advertised. So, buyer beware.