Marijuana component could ease pain from chemotherapy drugs

A chemical component of the marijuana plant could prevent the onset of pain associated with drugs used in chemo therapy, particularly in breast cancer patients, according to researchers at Temple University’s School of Pharmacy.

The researchers published their findings, “Cannabidiol Prevents the Development of Cold and Mechanical Allodynia in Paclitaxel-Treated Female C57Bl6 Mice,” in the journal Anesthesia and Analgesia.

The researchers developed animal models and tested the ability of the compound cannabidiol, which is the second most abundant chemical found in the marijuana plant, to relieve chemo-induced neuropathic pain, said Sara Jane Ward, research assistant professor of pharmaceutical sciences in Temple’s School of Pharmacy and the study’s lead author.

“We found that cannabidiol completely prevented the onset of the neuropathic, or nerve pain caused by the chemo drug Paclitaxel, which is used to treat breast cancer,” said Ward, who is also a research associate professor in Temple’s Center for Substance Abuse Research.

Ward said that one of cannabidiol’s major benefits is that, unlike other chemicals found in marijuana such as THC, it does not produce psycho-active effects such as euphoria, increased appetite or cognitive deficits. “Cannabidiol has the therapeutic qualities of marijuana but not the side effects,” she said.

Ward’s research has long focused on systems in the brain that are impacted by marijuana and whether those systems could be targeted in the treatment of various disorders. “Marijuana binds to the cannabinoid receptors in the body and researchers have long been interested in whether there is therapeutic potential for targeting this receptor system,” she said.

Ward became interested in this current study after attending a conference in which she learned about a pain state that is induced by chemo-therapeutic agents, especially those used to treat breast cancer, which can produce really debilitating neuropathic pain.

Cannabidiol has also demonstrated the ability to decrease tumor activity in animal models, said Ward, which could make it an effective therapeutic for breast cancer, especially if you “combined it with a chemo agent like Paclitaxel, which we already know works well.”

According to Ward, there are currently about 10 clinical trials underway in the United States for cannabidiol on a range of different disorders, including cannabis dependence, eating disorders and schizophrenia. Because of this, she believes it will be easier to establish a clinical trial for cannabidiol as a therapeutic against neuropathic pain associated with chemo drugs.

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In addition to Ward, Temple researchers involved in the study included Michael David Ramirez, Harshini Neelakantan and Ellen Ann Walker. The study was supported by grants from the National Institutes of Health and the Peter F. McManus Charitable Trust.

Temple University October 6 2011

Misuse of Pain Medication May Be Pathway to High-Risk Drug Behaviors

Philadelphia (July 22, 2011)—A new study by researchers at Drexel University’s School of Public Health suggests that abuse of prescription painkillers may be an important gateway to the use of injected drugs such as heroin, among people with a history of using both types of drugs. The study, published in the International Journal of Drug Policy, explores factors surrounding young injection drug users’ initiation into the misuse of opioid drugs. Common factors identified in this group included a family history of drug misuse and receiving prescriptions for opioid drugs in the past. The results support a need for efforts to prevent misuse of prescription drugs, particularly during adolescence.

“Participants were commonly raised in household where misuse of prescription drugs, illegal drugs, or alcohol, was normalized,” explains Dr. Stephen Lankenau, an associate professor in the School of Public Health and principal investigator of the study.  “Access to prescription medications – either from a participant’s own source, a family member, or a friend – was a key feature of initiation into prescription drug misuse.”

In numerous cases, the desire to experiment with a prescription opioid drug (the common class of drugs that includes codeine and oxycodone), combined with financial incentives or pressures from friends to sell available quantities, resulted in escalated patterns of opioid misuse, according to the study.

Lankenau and colleagues also describe two key findings as evidence of an emerging dynamic among misuse of opioid drugs and the use of injection drugs. First, four of five IDUs misused an opioid before injecting heroin, in contrast to more conventional patterns of using opioids as a substitute drug after initiating heroin use.

Second, in nearly one out of four young IDUs in this study, a prescription opioid was the first type of drug they injected. Prescription opioids are rarely reported at initiation into injection drug use amongst young IDUs. All but two of these participants later transitioned into injecting heroin.

Opioid misuse is an important public health concern due to the increasing association of opioids with drug dependence and fatal overdose, and much research has focused on the factors affecting how and when people initially misuse opioids. However, descriptive data about initiation into prescription opioid misuse among young injection drug users are scarce.

To fill this gap, in this study researchers interviewed 50 young IDUs aged 16 and 25 years old in New York and Los Angeles, who had misused a prescription drug at least three times in the past three months, to study contextual factors leading to their use of opioid drugs. Participants were recruited in natural settings, such as parks, streets, and college campuses, during 2008 and 2009. A mixed-methods research design was utilized that collected both quantitative and qualitative data.

Additional findings and descriptors of the study population include:

  • Most were white, heterosexual males in their early 20s
  • Many did not complete high school, were expelled from school, or held back a grade
  • Nearly all were homeless at some point, most were currently homeless, and most regarded themselves as “travelers,” (i.e., moving from city to city in search of work, housing, or adventure)
  • Most had received a psychological diagnosis, such as depression, anxiety, or Attention Deficit Hyperactivity Disorder (ADHD), and many had a history of drug treatment
  • Most generally regarded prescription opioids as readily accessible, valued commodities that could be traded or sold
  • Nearly three-quarters had been prescribed an opioid in their lifetime, which occurred on average at 14.6 years old, often for common ailments such as dental procedures or sports injuries
  • Most witnessed family members misuse one or more substances during childhood and adolescence, ranging from alcoholism to injecting heroin

The authors conclude that prevention efforts, especially during adolescence, are needed, and that parents and guardians need to carefully monitor and safeguard all prescription medications, particularly opioids, within the household. Although households where drug use is normalized or where broader social or psychological problems exist are more difficult to remedy with prevention efforts or policy changes, future research examining prescription opioid misuse among a range of adolescents and young adults to better understand the contextual and environmental factors of drug use may yield additional solutions.

The article was co-authored by Karol Silva (Drexel University); Michelle Teti (University of Missouri); Alex Harocopos (National Development and Research Institutes); and Jennifer Jackson Bloom and Meghan Treese (Children’s Hospital Los Angeles).

Lankenau is also principal investigator of two studies evaluating the effectives of overdose prevention programs in Los Angeles and Philadelphia.

Lankenau is an associate professor in the Department of Community Health & Prevention at the Drexel University School of Public Health.  He received his PhD and MA degrees in Sociology from the University of Maryland.  He earned his BA in Sociology at the University of Vermont.