Chronic pain is defined as pain lasting for longer than six months. Chronic pain is often the result of injury (ex: back pain due to a work accident) or illness (ex: arthritis, fibromyalgia, malignancy), and may persist for months or even years in some patients. The stresses that such pain creates impacts the social lives of patients, decreases ability to work and increases financial burden, and can lead to significant mental health disorders (ex: depression, anxiety, suicide). One study from the National Institutes of Health found that approximately 25.3 million American adults experienced pain every day during the previous three months and that a total of 126 million experienced significant pain within the past 3 months.  Unfortunately, patients are often prescribed opiates for this pain by providers that do not have enough experience with chronic pain or the available therapies. This has contributed to the national opioid epidemic, with almost 20,000 Americans dying from prescription opiates alone . Fortunately, there are multiple non-opioid medications available to combat this epidemic.
Medical Cannabis and Chronic Pain
Multiple studies have shown the benefit of medical cannabis and cannabis products for the treatment of chronic pain, and it is the most common condition that medical cannabis is prescribed for.  The highest quality review to of the medical literature to date included almost 2,500 patients with a multitude of medical conditions (ex: cancer, multiple sclerosis, neuropathy, etc) treated with various cannabis procuts (i.e. smoked/vaporized plant material, oral THC sprays, oral THC, and other oral medications). The review suggested that patients using cannabis products were 40% more likely to experience improvement in pain, with some evidence of a dose-dependent response.  A separate study found that patients on chronic opioids experienced a 27% reduction in pain scores without increasing opioid dosage.  Finally, unlike opioids, medical cannabis was shown to be a safe when the quality was controlled and experienced physicians and programs were utilized for care management. 
The Impact on Opioid Use and Overdose Mortality
There is evidence that patients who use cannabis for chronic pain are able to decrease opioid use, with one study from Michigan use associated with a 64% decrease in opioid use.  Another study from the University of Pennsylvania found that states with medical cannabis laws had a 24.8% lower average annual opioid overdose mortality rate compared to states without medical cannabis laws. Additionally, 60% of opioid overdoses occurred in users with prescriptions from a single doctor.  This work is made more clear by evidence that suggests that this benefit is only found in states with medical cannabis and dispensaries, but not those without dispensaries, showing that dispensaries and their staff may be crucial to providing maximum benefit.  With more research needed to confirm these studies, investigations to date have found that cannabis, especially in areas with dispensaries, has the potential to reduce opioid use rates and decrease overdose mortality.
The Market Today and Available Therapies
Unfortunately, unregulated cannabis and synthetic cannabis products (like K2 or spice) are often tainted with unwanted chemical or illegal drugs. There have been numerous news reports of overdoses, including a 2-day report of over 95 overdoses in New Haven alone in August of 2018. As such, it is important to always understand where your product is coming from and who is providing it to you. Additionally, based on the data above, it is important to involve both medical and cannabis specialists in order to provide optimal benefits. There are many products available in many forms (ex: oral liquids/solid, mucosal sprays, inhaled vapors, etc), with various concentrations of THC and CBD (the most common active ingredients). THC tends to have a more psychoactive profile than CBD, but both can have therapeutic qualities. In order to receive maximal benefit, it is important to discuss the treatment with your physician as well as your local dispensary-based pharmacist or technician. It is also important to regularly follow up with either or both for further adjustments of your regimen.
Hopefully, as research into this field continues and cannabis products become further optimized, the benefit will continue to grow.
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