An expert panel offers a "weak" recommendation for using medical marijuana to treat chronic pain. Photo by Circe Denyer/publicdomainpictures
Sept. 8 (UPI) -- Non-inhaled medical marijuana and its derivatives offer few benefits in treating chronic pain, leading a panel of experts to offer a "weak" recommendation for its use for the condition in an article published Wednesday by BMJ.
In more than 100 studies, marijuana-based pain treatments provided little or no improvement in patient self-reported pain intensity, physical functioning and sleep quality, the researchers said.
In addition, the therapies, most commonly available in pill form, oral solution or topical ointment applied to the affected areas, failed to produce improvements in emotional, work and family or social functioning, they said.
The recommendation applies to adults and children with all types of moderate to severe chronic pain and does not include smoked or vaped forms of cannabis and recreational cannabis.
It also does not address the drug's use as a pain treatment in patients who are receiving end-of-life care, according to the authors.
"Patients with persistent pain continue to search for new therapeutic options and often perceive cannabis as a worthwhile alternative," the authors of a commentary published with the recommendations wrote.
However, this recommendation indicates that there is only "moderate evidence of a clinically important decrease in pain for a small to very small proportion of patients" using the drug, they said.
The panel included international experts in the treatment of chronic pain, as well as three patients diagnosed with chronic pain conditions.
The use of medical marijuana, prescribed by a physician, has been legalized in 36 states, according to the National Conference of State Legislatures.
Medical marijuana, or medical cannabis, refers to medicinal therapies derived from the Cannabis sativa plant that rely on the effects of THC, or delta-9 tetrahydrocannabinol and CBD, or cannabidiol, to provide symptom relief, the Mayo Clinic says.
THC is the primary ingredient in marijuana that provides the "high."
Despite limited and often conflicting medical evidence, medical marijuana has been used to treat patients with conditions that range from Alzheimer's disease and cancer to epilepsy and glaucoma, the Mayo Clinic says.
Medical marijuana also has been used to treat severe and chronic pain, with some studies finding that it can help when it is smoked or vaped.
The new recommendation is based on a review of data from 32 clinical trials intended to explore the benefits and harms of medical cannabis or cannabinoids for chronic pain, as well as 39 studies of long-term safety, the authors said.
Their analysis also included 17 studies in which the drug was used as an alternative to opioids and 15 studies of patient satisfaction, they said.
Although no evidence linked medical marijuana with psychosis, the drug may cause reduced ability to concentrate, vomiting, drowsiness and dizziness, according to the authors.
Potential serious side effects, such as dependence, or addiction, as well as falls, suicidal thoughts and suicide were uncommon in the included studies, but more researchers is needed, the authors said.
In addition, little evidence exists that the drug reduced the use of opioid pain medications, which can be addictive, they said.
The recommendation for the use of medical marijuana for chronic pain is "weak" because of the close balance between benefits and harms, according to the authors.
However, the panel urged patients work with their doctors to make choices for treatment that reflect their values and personal needs, though physicians should emphasize the harms associated with vaping or smoking marijuana and discourage "self medication," the authors of the commentary added.
The panel suggested that researcher should explore issues such as optimal dosing and formulation.
"Although increasingly prescribed or authorized, medicinal cannabis or cannabinoids for chronic pain remains contentious for many physicians because of the suspected or known dangers associated with cannabis use," authors of the recommendation wrote.
"However, surveys show that physicians want more education and guidance around use of medical cannabis or cannabinoids as a potential pain management therapeutic," they said.