Effect of inhaled cannabis on pain in adults with sickle cell disease
Cannabis could be an effective way to reduce acute and chronic pain in patients with sickle cell disease, according to a small pilot study published in JAMA Network Open. Sickle cell disease affects millions of people around the world and is particularly common in those whose ancestors originated from sub-Saharan Africa.
Sickle cell disease is a genetic disease that affects about 100000 people in the United States, mostly of African or Hispanic origin. Their red blood cells are rigid and sickle-shaped, which causes blockages in blood vessels, deprives tissues and organs of oxygen, and causes periods of severe pain.
Sickle cell anemia and cannabis
Researchers from Irvine and San Francisco Universities recruited 23 adults with sickle cell disease in a placebo-controlled study to see if inhaled cannabis could be a safe addition to opioid drugs in treating sickle cell pain . Most patients continued to take opioids for the five days of the study. Participants inhaled either vaporized cannabis or a placebo three times a day. Cannabis had an equal ratio of CBD and THC.
Over the five days of the study, patients who inhaled cannabis reported that the pain interfered less and less with their daily activities, such as walking and sleeping, and that there was a significant drop in the intensity of pain affecting their mood. The decrease in pain levels, however, was not considered statistically significant.
Although the results are mixed, the researchers say their pilot study should pave the way for larger clinical studies on cannabis as a treatment for sickle cell anemia.
“The results of these trials show that vaporized cannabis appears to be generally safe,” said Kalpna Gupta, PhD, professor of medicine at UCI Irvine Center for the Study of Cannabis. “They also suggest that sickle cell patients could ease their pain with cannabis - and that cannabis could help society cope with the opioid-related public health crisis. Of course, we still need larger studies with more participants to give us a better idea of how cannabis might benefit people with chronic pain ”.
Opioid drugs have been the main treatment for sickle cell disease. But because many doctors are reluctant to prescribe opioids today for fear of addiction, overdose, and legal action, sickle cell patients have fewer options.
“In the current climate of heightened awareness of the ongoing opioid epidemic, it would have been encouraging if this study demonstrated a decrease in the use of chronic pain relievers during the active vaporizing phase of cannabis,” the researchers conclude. "The small sample size and the short duration of our study may have contributed to the inability to demonstrate a decrease in opioid use in participants receiving the active drug compared to placebo."
Of the 33 US states that have legalized medical cannabis, only four have included sickle cell disease as a qualifying condition. This forces many sickle cell patients to obtain cannabis from unauthorized sources.
“Pain causes many people to turn to cannabis and it is, in fact, the main reason people cite for looking for cannabis at dispensaries,” Gupta said. “We don't know if all forms of cannabis products will have a similar effect on chronic pain. The vaporized cannabis, which we have used, is perhaps safer than other forms because smaller amounts reach the circulation of the body. This trial opens the door to experimentation with different forms of medical cannabis to treat chronic pain ”.
A recent small study in Israel showed that very low “microdoses” of inhaled THC can significantly reduce chronic pain in patients with neuropathy, radiculopathy, phantom limb pain, or complex regional pain syndrome (CRPS ).