Chronic Pain and the Endocannabinoid System

If you live with chronic pain, you've probably seen bold claims about CBD and the endocannabinoid system online. The science behind this system is real and genuinely interesting, but the honest answer about what it means for your pain is more careful than the internet suggests. Let's walk through how the system works, what the research actually shows, and how to make a safe decision with your medical team.

If what you need today is the practical side, the "I'm doing everything right and I'm still in pain" side, start with why your pain treatments may not be helping. Then come back, and I'll show you what's going on under the hood.

What is the endocannabinoid system, in plain terms?

Gentle movement can support the body without forcing a fix.

The endocannabinoid system is a signalling network your body already runs. You can think of it as a set of volume knobs. It isn't a single organ you could point to on an anatomy chart. Instead, it's made of receptors on the surface of cells, small fatty messenger molecules that switch those receptors on, and enzymes that build and then break down those messengers. It's spread through your nervous system and your immune tissue.

Its job is to keep other systems from running too hot or too cold. It quietly nudges nerve signalling, immune response, appetite, mood, and sleep toward balance.

The name scares people, so here's what it means. "Endocannabinoid" simply refers to cannabinoid-like compounds your own body makes from the inside. The system was named after the plant that led researchers to discover it, but you had it long before you ever heard of it.

What do CB1 and CB2 receptors do?

The system works mainly through two receptors, CB1 and CB2. CB1 is the main type in the central nervous system (your brain and spinal cord), and cannabinoid signalling also acts at sites out in the rest of the body (International Journal of Molecular Sciences, via NIH).

• CB1, the brain and nerve receptor. These sit on nerve cells, especially in the parts of the brain and spinal cord that handle pain, movement, memory, and mood. Turning CB1 on generally makes nerve cells fire less freely. It's the receptor most linked with the "high" from THC, and with how pain signals are adjusted.
• CB2, the immune receptor. These show up more on immune cells and in tissue outside the brain, and there are more of them where there's injury or ongoing inflammation. CB2 activity leans toward calming the immune system rather than changing how you perceive things.

That split is helpful, but it isn't absolute. Both receptors turn up in more places than this summary suggests, and their numbers shift depending on the state of the tissue, which is part of what makes the system so hard to study.

What are anandamide and 2-AG?

An easy walk is often enough for one honest day.

These are your body's two best-known endocannabinoids, the messengers themselves. Anandamide gets its name from a Sanskrit word for bliss, and 2-arachidonoylglycerol is thankfully shortened to 2-AG.

What I find elegant is how they're made. Hormones like insulin or adrenaline are made ahead of time and stored until they're needed. Endocannabinoids aren't stored at all. Your body builds them from fatty parts of the cell membrane right when and where they're needed, uses them on the spot, and breaks them down within minutes. It's less like a broadcast through the bloodstream and more like a quiet, targeted conversation between two cells.

There's one more twist that explains the pain connection. This signalling mostly runs backwards. The nerve cell receiving a message makes the endocannabinoid and sends it back to the cell that sent the message, telling it to ease off. It's a feedback brake built right into the wiring.

How does it change the way you feel pain?

Pain isn't a single wire running from an injury to your brain. It's a signal that gets turned up or down at several checkpoints along the way, and endocannabinoid signalling shows up at more than one of them.

Researchers describe several ways cannabinoids adjust pain: reducing the chemical messengers released from nerve endings, changing how easily the receiving nerve fires, switching on pain-blocking pathways that run down from the brain, and reducing inflammation in nerve tissue (Frontiers in Pharmacology, via NIH). In plain language, it works on three levels:

• Out in the tissue, where a nerve ending meets an inflamed or injured area, signalling can quiet how insistently that nerve reports pain.
• At the spinal cord, the relay station that passes pain signals up to the brain, or doesn't. This is where that backwards feedback brake matters most.
• From the brain downward, where your brain runs its own pain-dampening circuits back down the spinal cord. Endocannabinoid activity helps switch those on.

This layered design is why pain researchers pay attention. The system doesn't remove pain, but it appears to be one of the ways your body sets the volume, and the volume is often what's gone wrong for people with long-standing pain. If you live with widespread pain and fatigue, this same idea runs through what I wrote about living well with fibromyalgia.

What about inflammation?

CB2 is the short answer. Immune cells carry these receptors, and their numbers tend to rise in inflamed tissue, almost as if the body is placing more brakes right where things are running hot.

Inflammation and pain feed each other. Inflammatory chemicals make nerve endings more sensitive, so the same touch or movement hurts more, and ongoing pain signals can stir up low-grade inflammation in nerve tissue. That loop is part of why long-standing pain gets so stubborn.

Reducing inflammation in nerve tissue is one of the mechanisms listed in that Frontiers in Pharmacology review. But showing that something happens in tissue isn't the same as showing a product helps a person, and that gap is where most health marketing quietly lives.

Is this real research, or just internet talk?

It's real. The National Academies of Sciences, Engineering, and Medicine, one of the most cautious bodies in American science, reviewed the evidence and concluded there's substantial evidence that cannabis is effective for treating chronic pain in adults (National Academies, via NIH Bookshelf). "Substantial evidence" is their second-highest level, and they used it sparingly across the whole report.

Chronic pain is also the most common reason people give for using medical cannabis, according to that Frontiers in Pharmacology review. People are already making this decision, often without a clinician in the conversation. Early in my career, I wasn't allowed to answer questions about any of this, but patients asked anyway. I'm glad that's changed, because silence never protected anyone. It just sent people to whatever the loudest website said.

What does the evidence say about CBD and chronic pain?

This is where we need to slow down, because the science of the system and the evidence for products are two different conversations.

A 2022 AHRQ-funded systematic review in the Annals of Internal Medicine pooled 18 randomized placebo-controlled trials with 1,740 participants and 7 cohort studies with 13,095 participants (Annals of Internal Medicine, via PubMed). Reviewers found short-term benefit, over one to six months, for certain high-THC products and products with similar amounts of THC and CBD, along with side effects like dizziness and sedation. For other products, and for longer periods, the evidence was missing or not strong enough to judge. So the benefit was short-term, limited to certain products, came with real side effects, and the long-term picture is still unknown.

The rules are just as clear. The FDA hasn't approved the cannabis plant for any medical use. The only FDA-approved purified CBD drug, Epidiolex, is approved for seizures linked to Lennox-Gastaut syndrome, Dravet syndrome, or tuberous sclerosis complex, and nothing else. THC and CBD products also can't legally be sold as dietary supplements (National Center for Complementary and Integrative Health, NIH). When someone tells you a bottle will handle your pain, they're ahead of both the evidence and the law.

Why is CBD product quality such a problem?

Because the label often isn't accurate. When researchers lab-tested 80 hemp-derived CBD products, 37 of them, or 46 percent, were off from their stated CBD amount by more than plus or minus 10 percent. Twelve had less than 90 percent of what the label claimed, and 25 had more than 110 percent (Journal of Cannabis Research, via NIH). NCCIH also warns that store-bought CBD may contain contaminants, including THC, which matters if you're drug tested at work.

If you and your medical team decide to explore CBD, these are the questions I'd want answered first:

• Is there a current certificate of analysis from an independent lab? You want a dated, third-party report that matches the batch number on your bottle, not the company's own claim.
• Does the report cover contaminants, not just strength? Pesticides, heavy metals, leftover solvents, and THC content should all be listed.
• Does the measured amount match the label? Given those testing results, it's a fair question.
• Is the company making disease claims? If the packaging says it treats a condition, the company is willing to break a rule you can see, so it's wise to be cautious.

Can CBD interact with your medications?

Yes, and this is the part that gets brushed aside most often. CBD is processed by the same liver pathways that handle many prescription medicines, so it can change how much of a drug ends up in your bloodstream.

One published case report described a serious interaction between CBD and the blood thinner warfarin. The patient's INR, a blood test that shows how long blood takes to clot, went up, and the warfarin dose had to be lowered (Epilepsy & Behavior Case Reports, via NIH). If you take warfarin, talk with your prescriber before anything else happens, not after.

Seizure medicines and sedatives deserve the same caution. Dizziness and sedation showed up as risks in that Annals review, and those effects add up with anything else that makes you drowsy. That raises the risk of falls, which is a real concern for anyone over sixty. Start low, go slow, and monitor closely, with your medical team watching.

I don't diagnose or prescribe, and nothing here is a recommendation to start or stop anything. Please talk with your physician and pharmacist before you add CBD or change any medicine.

One client's experience, and what it does and doesn't mean

I coach a woman living with Parkinson's disease who uses CBD and tells me she's noticed real improvements in how she feels. She brought it to her neurologist and pharmacist first, they reviewed her full medication list together, and she's kept them in the loop since.

That's one person's experience, and it isn't evidence. A single story can't separate a product from time, placebo response, or everything else changing in a life. CBD isn't an approved treatment for Parkinson's, so please don't read her story as a reason to expect the same result. If you live with Parkinson's, your movement-disorder team is the right place for this question, and you might also like my piece on gentle movement for Parkinson's.

What to ask your prescriber and pharmacist

Your pharmacist is one of the most underused experts in your life, and medication interactions are exactly their specialty. Bring your complete list of prescriptions, over-the-counter items, and supplements, and ask:

• Does this interact with anything I take, especially blood thinners, seizure medicines, or sedatives?
• Would it affect any liver tests or monitoring I already have?
• What side effects should make me stop and call you, like dizziness or unusual sleepiness?
• If we try it, how will we tell whether it's actually helping?

That last question matters most to me, because a plan with no way to measure it isn't really a plan. Bringing this to your doctor, rather than working around them, changes everything, which is the whole idea behind working with a health coach alongside your doctor.

A final thought

Understanding this system won't fix your pain on its own. But your body does have a built-in way to turn pain signals down, it's real and well mapped, and we still know far less than the marketing pretends about changing it from the outside. Knowing where the evidence stops lets you make a decision you can stand behind, with your medical team beside you.

For the practical companion to all this, read why your pain treatments may not be helping, and if pain has your nervous system running hot, how chronic stress affects your body fills in the other half. If you'd like help sorting real information from the noise, you can book a free discovery call with me. There's no pressure and no product to sell, just a nurse who'll tell you the truth, neighbor to neighbor. And on harder days, the free calming tools in the Sanctuary are always there.

With Care, Cheri Sacks, R.N., B.S.N., C.D.C.E.S., "Your Neighbor, The Nurse"

Related reading

• Why Your Pain Treatments Are Not Helping
• Living Well With Fibromyalgia
• How Chronic Stress Affects Your Body
• Gentle Movement for Parkinson's
• How to Work With a Health Coach and Your Doctor