Should I use CBD/Marijuana for chronic pain?
The answer is maybe. Marijana or Cannabis is a natural product which has been used for thousands of years. It has hundreds of ingredients but the most important ones are CBD and THC. Although it has been around for a very long time, we know relatively little about it compared to most medications. Unlike medications which have to go through a drug approval process by Health Canada which require proof of safety and effectiveness , marijuana was legalized in the same way alcohol was legalized in the USA after prohibition. So to sum up natural does not mean safe (tobacco is natural too) and we know relatively little about it because it only became legal recently. There are some studies to support its use in variety of pain related conditions, however often these are small studies of short duration. Also, any safety studies are of short duration and may miss side effects which develop over long term.
Keeping these limitations in mind this is what I normally tell my patients about marijuana. First of all one should not take it under the age of 25 or if there is any history of psychosis/ schizophrenia/hallucinations in the patient or their family, because Marijuana has been known to trigger psychosis especially in younger people. Second it is far safer than high dose opioids because it can not suppress breathing. Dying from overdose of Marijuana is highly unlikely. My third point is that it does not work better than most non-opioid medications for chronic pain on average, however on individual basis some respond better to medications and some respond better to Marijuana. The strongest evidence for Marijuana is in neuropathic pain (nerve pain), however it can also work for other painful conditions ranging from migraines to fibromyalgia. If one is to use Cannabis, CBD is preferable to THC containing product from safety perspective, however realistically even though patients may start with low dose pure CBD product, gradually the dose is often raised and THC added for effectiveness. The route of administration matters too. Oral oils are preferred to vaping which in turn is preferred to smoking Cannabis. There is evidence that smoking Cannabis can damage lungs. Depending on route of ingestion the benefit and side effects of Cannabis can last from a 2-10 hours. As Cannabis can affect reaction time, driving is not advised for 4(if smoked)-8 (if ingested) hours after marijuana use especially if still feeling “high”.
Other issues to keep in mind is that Marijana is produced from a plant, just like wine, and so there may be variability in effectiveness and side effects from batch to batch and from brand to brand. Once you find a brand you like try to stick with it. Also, marijuana is not a drug, and therefore it is not covered by most drug plans. As most patients who take it for chronic pain are likely to continue taking it for many years, the cost over lifetime can be substantial especially if patient is using high doses.
To sum up Cannabis is not a silver bullet for chronic pain, however it can be helpful for the right person especially if they tried and failed other approaches to pain management.