How Does Cannabis Measure up to Post-Op Pain

New research suggests cannabis may be able to help post op pain.

The ‘buzz’ around medical cannabis is often fixed on chronic, long-lasting pain. However, research suggests that cannabis may also help control post op pain, opening the door for additional acute pain cannabis treatments.

Pain control is of paramount importance following surgery. However, not all surgical patients can handle the powerful opioids that are often prescribed to deal with post-operative pain. This could include patients with a lower tolerance for pain drugs, or those with a previous history of drug abuse. Thereby, it is important to have alternatives for managing post op pain.

Although cannabis has emerged as a treatment for chronic pain in recent years, there is a paucity of research that has investigated the efficacy of cannabis for managing post op pain. So what does the available evidence tell us about future cannabis-based acute pain management?

Cannabis Before Surgery Can Be Problematic 

Before diving into the literature, it is important to note that while there may be some benefit to cannabis following surgery, cannabis before surgery can be problematic. In a study published in the Journal of the American Osteopathic Association (2019), the researchers investigated whether regular cannabis consumption had any effect on the amount of anesthetic needed for sedation during medical procedures. ^[1]Twardowski, M. A., Link, M. M., & Twardowski, N. M. (2019). Effects of cannabis use on sedation requirements for endoscopic procedures. Journal of American Osteopathic Association, 119(5), … Continue reading

In a retrospective study design, the researchers reviewed two-hundred and fifty medical records from one endoscopy center located in Colorado, where state-wide recreational cannabis sales became legalized in 2012. They compared the records of regular cannabis consumers to the records of non-consumers. The findings suggested that regular cannabis consumers required a significantly higher dose of anesthetic for sedation compared to non-consumers, and these results persisted when the researchers controlled for the factors of age, sex, alcohol use, and other drugs.

Cannabis-consuming patients required an additional fourteen percent fentanyl, approximately twenty percent more midazolam, and a staggering two-hundred and twenty percent increase in propofol.

Although coming from a retrospective design, these findings highlight the importance of being up-front with your anesthesiologist and wider circle of care about cannabis consumption. Withholding that information may negatively impact an important surgical procedure. However, some research suggests that cannabis following surgery can be beneficial.

Study Finds That Cannabis Alleviates Post Op Pain

In a study published in Anesthesiology: The Journal of the American Society of Anesthesiologists (2006), the researchers tested whether a standardized cannabis plant extract could provide acute pain relief following surgery.^[2]Holdcroft, A., Maze, M., Dore, C., Tebbs, S., & Thompson, S. (2006). A multicenter dose-escalation study of the analgesic and adverse effects of an oral cannabis extract (Cannador) for … Continue reading The surgical patients received either five, ten, or fifteen milligrams of cannabis extract. If the cannabis extract did not provide enough pain relief, the researchers gave the patients ‘rescue analgesia’. The results indicated that with increasing doses of cannabis, there was an increase in pain relief.

All eleven patients in the five-milligram dose group requested rescue analgesia, fifty percent of patients in the ten-milligram group, and only twenty-five percent of patients in the fifteen-milligram group. Unsurprisingly, the fifteen-milligram group reported the greatest level of pain relief, but average scores peaked at approximately two hours and then declined with each additional hour. Despite oral administration that is known to have effects that last for hours, patients may require additional doses after only two hours for continued pain relief.

Can CBD Control Post Op Inflammation? 

Inflammation is a part of the natural healing process for all injuries. ^[3]Arias, J. I., Aller, M. A., & Arias, J. (2009). Surgical inflammation: a pathophysiological rainbow. Journal of Translational Medicine, 7(1), 19. Depending on the type of surgery, a patient could experience severe inflammation and therefore, severe pain. In addition to pain-killing drugs like opioids, post-operative care will often involve the administration of anti-inflammatory drugs.

Cannabis might be able to tackle both of these post op ‘side effects’. Clinical studies have shown that THC is primarily responsible for cannabis-related pain relief, but its non-psychoactive counterpart, CBD, is primed for anti-inflammatory duties. Clinical research has demonstrated that due to the strong expression of cannabinoid receptors in the immune system, CBD reduces the levels of pro-inflammatory cytokines. ^[4]Atalay, S., Jarocka-Karpowicz, I., & Skrzydlewska, E. (2020). Antioxidative and anti-inflammatory properties of cannabidiol. Antioxidants, 9(1), 21. It is possible that future post op care packages might include a THC/CBD combo for treating surgical pain and inflammation. However, a substantial amount of clinical research needs to happen first.

A Lack of High-Quality Evidence Remains

The previously mentioned 2006 study is promising but is far from the gold-standard scientific evidence required to alter current medical practice. Overall, the amount of evidence is small. A 2017 systematic review published in Pain Physician highlighted the relatively few high-quality studies that have investigated the efficacy of cannabis for treating post op pain.(Aviram, J., & Samuelly-Leichtag, G. (2017). Efficacy of Cannabis-Based Medicines for Pain Management: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Pain Physician, 20(6), E755-796.))

The researchers could only include three randomized controlled trials into the review, and those studies produced results indicating that cannabis-based medicines were not effective for post op pain. With only three studies included, the researchers advised that further investigation takes place. We need safe and effective alternatives for those who cannot tolerate traditional post op pain management. Large-scale, high-quality research studies are the only way that we are going to get there.