Medical marijuana could help patients reduce pain with opiates

December 6, 2011

Science Daily/University of California - San Francisco

A UCSF study suggests patients with chronic pain may experience greater relief if their doctors add cannabinoids -- the main ingredient in cannabis or medical marijuana -- to an opiates-only treatment. The findings, from a small-scale study, also suggest that a combined therapy could result in reduced opiate dosages.

More than 76 million Americans suffer from chronic pain -- more people than diabetes, heart disease and cancer combined, according to the National Centers for Health Statistics.

"Pain is a big problem in America and chronic pain is a reason many people utilize the health care system," said the paper's lead author, Donald Abrams, MD, professor of clinical medicine at UCSF and chief of the Hematology-Oncology Division at San Francisco General Hospital and Trauma Center (SFGH). "And chronic pain is, unfortunately, one of the problems we're least capable of managing effectively."

In a paper published this month in Clinical Pharmacology & Therapeutics, researchers examined the interaction between cannabinoids and opiates in the first human study of its kind. They found the combination of the two components reduced pain more than using opiates alone, similar to results previously found in animal studies.

Researchers studied chronic pain patients who were being treated with long-acting morphine or long-acting oxycodone. Their treatment was supplemented with controlled amounts of cannabinoids, inhaled through a vaporizer. The original focus was on whether the opiates' effectiveness increased, not on whether the cannabinoids helped reduce pain.

"The goal of the study really was to determine if inhalation of cannabis changed the level of the opiates in the bloodstream," Abrams said. "The way drugs interact, adding cannabis to the chronic dose of opiates could be expected either to increase the plasma level of the opiates or to decrease the plasma level of the opiates or to have no effect. And while we were doing that, we also asked the patients what happened to their pain."

Abrams and his colleagues studied 21 chronic pain patients in the inpatient Clinical and Transitional Science Institute's Clinical Research Center at SFGH: 10 on sustained-release morphine and 11 on oxycodone. After obtaining opiate levels from patients at the start of the study, researchers exposed them to vaporized cannabis for four consecutive days. On the fifth day, they looked again at the level of opiate in the bloodstream. Because the level of morphine was slightly lower in the patients, and the level of oxycodone was virtually unchanged, "one would expect they would have less relief of pain and what we found that was interesting was that instead of having less pain relief, patients had more pain relief," Abrams said. "So that was a little surprising."

The morphine group came in with a pain score of about 35, and on the fifth day, it decreased to 24 -- a 33 percent reduction. The oxycodone group came in with an average pain score of about 44, and it reduced to 34 -- a drop of 20 percent. Overall, patients showed a significant decrease in their pain.

"This preliminary study seems to imply that people may be able to get away perhaps taking lower doses of the opiates for longer periods of time if taken in conjunction with cannabis," Abrams said.

Opiates are very strong powerful pain medicines that can be highly addictive. They also can be deadly since opiates sometimes suppress the respiratory system.

As a cancer doctor, Abrams was motivated to find safe and effective treatments for chronic pain. Patients in the cannabis-opiates study experienced no major side effects such as nausea, vomiting or loss of appetite.

"What we need to do now is look at pain as the primary endpoint of a larger trial," he said. "Particularly I would be interested in looking at the effect of different strains of cannabis."

For instance, Delta 9 THC is the main psychoactive component of cannabis but cannabis contains about 70 other similar compounds with different effects. One of those is cannabidiol, or CBD. It appears to be very effective against pain and inflammation without creating the "high" created by THC.

"I think it would be interesting to do a larger study comparing high THC versus high CBD cannabis strains in association with opiates in patients with chronic pain and perhaps even having a placebo as a control," Abrams said. "That would be the next step."

Abrams is the lead author of the paper; co-authors are Paul Couey, BA, and Mary Ellen Kelly, MPH, of the UCSF Division of Hematology-Oncology at SFGH; Starley Shade, PhD, of the UCSF Center for AIDS Prevention Studies; and Neal Benowitz, MD, of the UCSF Division of Clinical Pharmacology and Experimental Therapeutics.

The study was supported by funds from the National Institutes on Drug Abuse (NIDA), a subsidiary of the National Institutes of Health (NIH).

Major Components of Cannabis

·     Delta-9 Tetrahydrocannabinol (Delta-9 THC)-- It is the main psychoactive component of cannabis with mild to moderate painkilling effects. It also helps treat nausea associate with cancer chemotherapy and to stimulate appetite. It induces feelings of euphoria. Potential side effects include accelerated heartbeat, panic, confusion, anxiety and possible paranoia.

·     Cannabidiol (CBD)- It is a major, non-psychoactive component of cannabis that helps shrink inflammation and reduce pain without inducing the euphoria effects of THC. It has been used to treat rheumatoid arthritis, inflammatory bowel diseases, psychotic disorders and epilepsy. Larger amounts of CBD can relax the mind and body without causing negative side effects associated with THC.

·     Cannabinol (CBN)-- It is a secondary psychoactive component of cannabis. It is not associated with painkilling effects of THC or CBD. CBN is formed as THC ages. Unlike the euphoria effects of THC, CBN can induce headaches and a sense of lethargy.

·     Tetrahydrocannabivarin (THCV) -- It is found primarily in strains of African and Asian cannabis. THCV heightens the intensity of THC effects and the speed in which the component is delivered, but also causes the sense of euphoria to end sooner.

https://www.sciencedaily.com/releases/2011/12/111206151448.htm

Legalized medical cannabis lowers opioid use

April 2, 2018

Science Daily/University of Georgia, School of Public and International Affairs

States that have approved medical cannabis laws saw a dramatic reduction in opioid use, according to a new study by researchers at the University of Georgia.

In a paper published today in the Journal of the American Medical Association, Internal Medicine, researchers examined the number of all opioid prescriptions filled between 2010 and 2015 under Medicare Part D, the prescription drug benefit plan available to Medicare enrollees.

In states with medical cannabis dispensaries, the researchers observed a 14.4 percent reduction in use of prescription opioids and nearly a 7 percent reduction in opiate prescriptions filled in states with home-cultivation-only medical cannabis laws.

"Some of the states we analyzed had medical cannabis laws throughout the five-year study period, some never had medical cannabis, and some enacted medical cannabis laws during those five years," said W. David Bradford, study co-author and Busbee Chair in Public Policy in the UGA School of Public and International Affairs. "So, what we were able to do is ask what happens to physician behavior in terms of their opiate prescribing if and when medical cannabis becomes available."

Since California approved the first medical cannabis law in 1996, 29 states and the District of Colombia have approved some form of medical cannabis law.

"Physicians cannot prescribe cannabis; it is still a Schedule I drug," Bradford said. "We're not observing that prescriptions for cannabis go up and prescriptions for opioids go down. We're just observing what changes when medical cannabis laws are enacted, and we see big reductions in opiate use."

The researchers examined all common prescriptions opiates, including hydrocodone, oxycodone, morphine, methadone and fentanyl. Because heroin is not a legal drug, it was not included as part of the study.

Last year, the U.S. Department of Health and Human Services declared a public health emergency related to the abuse of opiates. Opioid overdoses accounted for more than 42,000 deaths in 2016, more than any previous year on record, and more than 40 percent of opioid overdose deaths involved a prescription opioid, according to HHS.

Opioid prescription rates increased from about 148 million prescriptions in 2005 to 206 million prescriptions by 2011, Bradford said. This coincided with an increase in the number of opioid-related deaths.

"There is a growing body of literature that suggests cannabis may be used to manage pain in some patients, and this could be a major component of the reductions we see in the use of opiates," he said.

The researchers did not, however, see any significant reductions in the number of non-opioid drugs prescribed during the study period.

"In other studies, we examined prescription rates for non-opioid drugs such as blood thinners, flu medications and phosphorus stimulants, and we saw no change," said Ashley Bradford, lead author of the study and graduate student in UGA's department of public administration and policy. "Medical cannabis wouldn't be an effective treatment for flu or for anemia, so we feel pretty confident that the changes we see in opioids are because of cannabis because there is a legitimate medical use."

The researches concede that if medical cannabis is to become an effective treatment, there is still much work to be done. Scientists are only just beginning to understand the effects of the compounds contained in cannabis, and an effective "dose" of cannabis would need to be defined clearly so that each patient receives a consistent dose.

"Regardless, our findings suggest quite clearly that medical cannabis could be one useful tool in the policy arsenal that can be used to diminish the harm of prescription opioids, and that's worthy of serious consideration," David Bradford said.

Coauthors on the paper Amanda Abraham, assistant professor of public administration and policy at UGA and Grace Bagwell Adams, assistant professor of health policy and management in UGA's College of Public Health.

https://www.sciencedaily.com/releases/2018/04/180402202236.htm