Have you ever heard , “Is cannabidiol (CBD) a painkiller?” To answer simply, “Yes, it is (with caveats), or at the very least a pain distractor.” Either way, we still need more data to show if this is the case for definite. For some, CBD may work; for others, CBD on its own may not be effective. There are various studies on both animals and humans showing that CBD can reduce inflammation, which usually translates to “less pain”. Here is some more information on CBD …

How Does CBD Work for Pain?

CBD was once thought to be a CB2 receptor agonist, but more recent research suggests that it is an indirect antagonist of both the CB1 and CB2 receptors as well as an antagonist of the G protein-coupled receptor (GPR), GPR55. The antidepressant and anxiolytic effects of CBD are thought to be due to it acting as a partial agonist of the 5HT1A serotonin receptor. CBD is an inverse agonist of GPR3 (maintains meiotic arrest), GPR6 (promotes neurite growth) and GPR12 (disruption of which is thought to cause obesity).

Some research suggests that the pharmacological action of CBD is due to its inhibition of the enzyme, fatty acid amide hydrolase (FAAH), which increases the amount of anandamide available in the body. CBD is metabolized in the liver and gut by cytochrome P2C19 (CYP2C19) and cytochrome P3A4 (CYP3A4) enzymes, as well as UDP glucuronosyltransferase (UGT) gene types UGT1A7, UGT1A9 and UGT2B7 isoforms. CBD desensitizes CYP450.

CBD has also been shown to be an allosteric modulator of the mu- and delta- opioid receptors. The combination of action on both serotonin and opioid receptors could be one major reason why CBD works for pain. CBD and its acidic precursor, cannabidiolic acid (CBDA) also selectively inhibits cyclooxygenase (COX)-2 activity. This is similar to how non-steroidal anti-inflammatories (NSAIDs) such as ibuprofen work, and is another major reason why CBD and CBDA work to beat pain (as well as breast cancer cells).

There is some suggestion that CBD, like THC, mimics the two endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in a rough rather than precise way, as like these two endocannabinoids both THC and CBD modulate CB1 and CB2 receptors.

CBD “vs.” THC for Pain

Many people want to avoid THC and say “I just want the CBD”. The idea that the two compounds are at odds with one another or do not work in tandem with each other is short-sighted at best. There is some suggestion that high doses of CBD can counteract or balance the effects of THC, but at the same time, CBD can potentiate the effects of THC by increasing CB1 receptor density. This could be one reason why strains high in THC with some CBD may have longer lasting but generally more tolerable effects, whilst strains with little-to-no CBD can have more of a psychoactive effect, but does not last as long.

There is also some suggestion that, in order for CBD to be truly effective for pain, it must be used in conjunction with THC, even non-psychoactive amounts. The reasoning behind this is the THC “allows” CBD to cross the blood-brain barrier, but whether or not this is true remains to be seen. However, CBD and THC definitely do work with each other in very unique ways, with the dosage of each affecting the way the other behaves. To give a simple key:

  • Low CBD + Low THC = Likely to have little-to-no psychoactive effect.

  • High CBD + Low THC = Likely to have little-to-no psychoactive effect.

  • Equal parts CBD and THC = May have some psychoactive effect, but not for all. CBD seems to “balance out” THC’s psychoactivity.

  • High CBD + High THC (where THC is still the cannabinoid found in higher concentrations) = Long-lasting psychoactive effects, but not as strong as strains or products containing no CBD. This ratio type is often, but not exclusively, found in indica strains. Myrcene also tends to be more abundant in indicas, which may contribute to their “couchlock” effects. Also, the CBD may be one reason why indica strain types tend to reach a ceiling - i.e. after ingesting a certain amount, one cannot get “higher” or “more stoned”.

  • Low/No CBD + High THC = Strong, short-lasting psychoactive effect. Ratio type is often found in sativa strain types, where terpenoids such as beta-caryophyllene and limonene seem to be most common. Sativa strains from the equatorial region are also more likely to contain the cannabinoid tetrahydrocannabivarin (THCV), which curbs the psychoactivity of THC in small doses but potentiates it in high doses. This combination of terpenoids and cannabinoids suggests a major reason why sativas tend to have the effect they do - clear-headed, stimulating and energetic, but short-lived. However, the more that is ingested, the more “high” or “stoned” one gets, as the THCV potentiates THC and there is little or no CBD to “calm” the other two down.

THC also has anti-inflammatory and painkilling/distracting properties of its own. For those with severe inflammation, and where the pain may be too much to bear, the psychoactive effects may even be desirable to a certain extent, as long as the effect is controllable and not too overwhelming - which is why 1:1 CBD:THC ratios may be particularly useful for chronic pain. However, in such instances, it may be best to think of THC as therapeutic as opposed to psychoactive, as psychoactive amounts are not necessarily even used, or what would normally be a psychoactive amount of THC is balanced out by CBD.

Whilst CBD on its own may work for some people, this is not necessarily the case for everyone. Some people - condition and physiology dependent - may require a certain amount of THC in order to get the full anti-inflammatory and pain killing effects of CBD. Another scenario could be that CBD may work for many people in a low amount of chronic pain, but not necessarily those who are in moderate-to-severe levels of chronic pain.

CBD Oil for Back Pain

An estimated 9 out of every 10 US adults will face some sort of back pain in their lifetimes. Back pain has many causes, and it is the leading cause of disability worldwide. Heat therapy, massage, acupuncture and spinal manipulation are often the first step/s of treatment.

Medications such as NSAIDs, skeletal muscle relaxers, steroidal injections and opioids are also used, but in many instances their efficacy still needs to be proven. Surgery is often a last resort, and is usually only carried out for conditions such as degenerative disc disease, severe myelopathy, spinal hematomas and other such severe back problems.

As there are few medications available that have been proven effective for back pain, as well as such medications causing some severe negative side effects, there is a serious need for safe medications. Could cannabis and cannabinoids such as CBD be one of them?

Again, the answer is “potentially”. The mechanisms for why CBD work for back pain are similar to how it could be useful for pain in general - i.e. it is an anti-inflammatory, allosteric modulator of opioid receptors and is a partial agonist of the 5HT1A serotonin receptor. Furthermore, CBD may help reverse bone loss and help heal fractured bones. CBD infused in oils such as coconut and olive oil may also help provide lubrication for the bones.

There is a lot of potential for cannabinoids to be helpful for back pain. The question asks, “what sort of back pain?” Where CBD may be useful for one type of back pain, it may not be for others. There are already several types of medication that are prescribed for back pain that are suitable for other types of pain, but have little or moderate, short-term efficacy. In this regard, cannabinoids could be similar, but with one added advantage: naturally-derived cannabinoids are far safer than many other medications.

CBD Oil for Nerve/Neuropathic Pain

As with back pain, there are few effective medications available. Antidepressants are often the first port-of-call when it comes to medications for nerve pain, in particular tricyclic antidepressants and serotonin-norepinephrine reuptake inhibitors (SNRIs, e.g. duloxetine). In more severe cases, antiepileptic medications such as gabapentin, pregabalin and sodium valproate are used, but these can have severe negative side-effects. As with back pain, capsaicin cream may be used.

The evidence for the efficacy of CBD for nerve pain is mixed, but there are some very good reasons for believing that CBD and other cannabinoids are useful for nerve pain. That CBD is an inverse agonist of GPR6 could explain why it is useful for Alzheimer’s and Parkinson’s disease. At the same time, neuropathic pain may be caused by a malfunctioning or overactive vanilloid receptor (aka TRPV1 or the capsaicin receptor). CBD desensitizes this receptor, which is another reason why it may help beat neuropathic pain.

Moreover, CBD has been shown to have neuroprotective effects, meaning that it could potentially help prevent neuronal damage and degeneration. Terpenes such as beta-caryophyllene (which is also a cannabinoid, as it is a CB2 receptor agonist) also have neuroprotective and painkilling properties.

CBD Hemp Oil for Pain

Many people do not have access to medical cannabis, and so they look to alternatives. The biggest alternative at the moment is hemp-derived CBD, infused into coconut or olive oil. This is because, in many places, hemp-derived CBD is legal, whilst CBD derived from psychoactive cannabis plant is illegal (even if it contains no THC in it). Also, for those who are looking to avoid psychoactive effects, hemp-derived CBD seems to be the perfect choice.

There are several issues with this approach, including:

  1. There is a severe lack of regulatory oversight of hemp-based products in the USA. Sadly, there are many products on the hemp CBD market that contain dangerous levels of pathogens (mold, mildew, bacteria etc.), pesticides, pollutants and heavy metals. This is due to the fact that, in many instances, the hemp used to make such products is grown for industrial purposes. As hemp is a supersucker of whatever is in the soil, it picks up all the industrial chemicals used on that land.

CBD products from Europe fair better in this regard, as products containing CBD are considered healthcare products and are regulated as such, but there are still some issues regarding safety.

  1. Many products do not have the amount of CBD they claim to have on the label. The FDA has issued warnings about this, even to companies considered nominally “good”.

  2. Furthermore, many companies may sell CBD products (in particular tinctures) with ineffective amounts of CBD.

  3. As hemp is grown for fiber, it does not produce as many cannabinoids as a cannabis plant. This means harsher extraction methods may need to be used, which in turn means more plant waxes in the final product. Ingesting too many of these plant waxes may cause problems such as urinary tract infection (UTI).

  4. There is some suggestion that low doses of CBD and cannabidivarin (CBDV) may actually damage cells and be a potential factor in causing cancer.

  5. Further to the above, hemp-derived CBD products may not contain some of the cannabinoids that can mitigate some of the damage caused by other cannabinoids.

  6. In some instances, THC may be needed in order for the CBD to be truly effective.

Now, the cannabis plants that are grown for dispensaries may have many of the same issues as above, but interestingly enough, it is arguable that the quality of the products is several orders of magnitude better, as the regulations surrounding it are stricter (even if it is federally illegal)! In California at least, the products on the shelves go through some rather stringent safety tests, and the testing regime has improved significantly over the past few months.

Another factor to consider is that those who are growing cannabis plants for medical purposes are more likely to take care of their plants, whilst those making CBD products of their growing-for-industrial-purposes are more likely just looking for a way to make extra money out of their byproducts.

Now, we do not wish to say there are not any good hemp-derived CBD products out on the market. In fact, there probably are. The problem is that CBD has become a bit of a buzzword and, in a loosely regulated market, there are a lot of snake oil salesmen around who are willing to make a quick buck making some rather tall claims. As such, if you want CBD products of the highest quality (and probably of comparable or even cheaper prices), then it is worth getting a recommendation letter, medical marijuana card, and heading over to a good dispensary.

CBD Creams and Topicals

Cannabinoids do not have to be taken internally in order to have medical uses. For some conditions, such as psoriasis, eczema, acne, localized nerve pain and melanomas, a topical cream or salve may be just as useful. CBD creams may be particularly useful for joint pain and inflammation, which is common in psoriasis. As for skin cancers, there is some evidence suggesting that cannabinoids could essentially tell the melanoma to “self destruct”.

However, in some instances, CBD on its own is not enough even when in topical form, and THC is needed. However, as it is being applied topically, there is no psychoactive effect. Topicals and salves - unlike transdermal patches - only penetrate the first two layers of skin, so cannabinoids do not get into the bloodstream.

That is all for now. If you’d like to know more, check out our conditions page and/or buy our book! CBD is a complex compound with a very complex pharmacology, like all other cannabinoids. There is still lots to be discovered about how it works and what illnesses and injuries it could be used for. Keep your eyes peeled, and keep reading Leafwell to learn more about CBD and the cannabis plant as a whole.