Healing of a Chronic Pressure Injury in a Patient Treated With Medical Cannabis for Pain and Sleep Improvement: A Case Report

More than 100 cannabinoids have been isolated from the cannabis plant; of these, tetrahydrocannabinol (THC) and cannabidiol (CBD) are the best studied and have potential applications in pain management, epilepsy, sleep disorders, and other conditions.¹ It has been hypothesized in 2 review articles^2,3 that THC and CBD may accelerate wound healing due to their anti-inflammatory and analgesic effects. Inflammation is a critical stage of the immune response that serves to localize and eliminate invading pathogens and remove damaged tissue.⁴ It is characterized by the recruitment of immune cells to the site of injury through the release of chemotactic molecules such as cytokines, chemokines, histamine, and other mediators of inflammation.⁴ Prolonged or excessive inflammation, however, can be a cause of damage and prevent wound healing.⁵

It has been hypothesized that the binding of CBD to CB2 receptors in the skin lessens the response to histamine and downregulates the secretion of proinflammatory cytokines (including interleukin-1a [IL-1a], IL-1b, and tumor necrosis factor-⍺) by active immune cells, leading to decreased inflammation.⁶ An in vitro molecular study showed that CBD inhibited tumor necrosis factor-α–induced release of skin proinflammatory mediators in cultured HaCaT keratinocytes.⁷ In vivo studies reinforced these results, finding that administering CB2 agonists to a mouse model of systemic sclerosis reduced cutaneous inflammation and fibrosis and accelerated re-epithelization in a wound healing model.^8,9

The activation of CB1 receptors, which are highly expressed in the central nervous system, mediates pain perception.¹⁰ A case series reported that CBD oil applied topically in patients with epidermolysis bullosa, a painful genodermatosis characterized by blistering and wounding, accelerated wound healing, decreased blistering, and lessened pain in 3 cases of self-initiated use.⁶ In open-label trials, topical treatments containing THC and CBD, along with other components, were found to promote integumentary wound closure in 33 patients with uremic calciphylaxis, 2 patients with non-uremic calciphylaxis, and 1 patient with leg ulcers due to sickle cell disease.^11–13 Similar beneficial outcomes were reported in a retrospective study investigating the therapeutic effect of topical CBD-enriched ointment in 20 patients with chronic skin diseases, including psoriasis and atopic dermatitis.¹⁴ The current case report describes the use of 3 medical cannabis oils in a patient with a painful pressure injury (PI) and resultant sleep disturbance.

A 37-year-old woman was referred to a neurology clinic in Toronto, Canada. The patient had a medical history of multiminicore disease, scoliosis, short-chain acyl-CoA dehydrogenase deficiency, and epilepsy. Ten (10) years before referral, the patient experienced a stroke and consequently used a wheelchair and required continuous caregiver assistance. At the time of referral, the patient was taking gabapentin, zopiclone, aspirin, progesterone, and vitamins B₂, C, and D.

The patient had difficulty falling and remaining asleep, partially due to uncontrolled pain. She reported a usual bedtime of midnight followed by a long sleep latency. She described waking up several times throughout the night due to pain, most notably from a PI of unrecorded size between her right iliac crest and right rib cage that had progressively worsened for approximately 5 years before consultation (Figure 1). The wound had been caused initially by the patient leaning on the wheelchair armrest due to scoliosis. Multiple interventions to heal this wound, including various wound dressings, antibiotics, and topical ointments, were unsuccessful in reducing the pain or size of the wound. Because the PI had persisted for 5 years, the patient could not provide an account of all the dressings that had been used and patient records did not contain these details.

The patient was referred to the Neurology Centre of Toronto (NCT) and seen by the Virtual Medical Cannabis Clinic on August 7, 2020, for an initial consultation. The primary goal for medical cannabis was pain management and sleep improvement (quality and duration). The patient was treated with a protocol of 3 medical cannabis oils taken orally: a CBD-dominant oil (Yellow Cannabis Oil, 1:20 THC:CBD; Spectrum Therapeutics) for daytime use and 2 THC-dominant oils (Red No. 1 Oil, 26.3:0 THC:CBD, and Red No. 2 Oil, 26.3:0 THC:CBD; Spectrum Therapeutics) for use in the daytime and before going to sleep. Table 1 shows the complete THC/CBD titration schedule. Table 2 shows the quantities of oils used to achieve this schedule. Table 3 shows the terpene profiles of the cannabis oils used. After commencing the medical cannabis protocol, the patient reported improved sleep quality (measured by documented self-reported accounts of sleep latency and quality measured by frequency of nighttime awakenings) and decreased pain and anxiety.

Within 2 weeks of beginning the medical cannabis titration protocol, the patient, her caregiver, and primary care physician noted rapid improvements in the PI. The patient reported less wound pain, and both the caregiver and primary care physician reported reduced wound size and diminished redness. Approximately 1 month after beginning medical cannabis, the wound had reduced significantly in size and depth (Figure 2). After 2 months, it had almost completely healed (Figure 3). Unfortunately, because wound healing was an unexpected effect of cannabis use, details of the wound were not recorded. The photos were taken because the patient wanted to document the healing; this is why they do not contain image scale information.

Apart from the cannabis titration regimen, the only other change in lifestyle or medical treatment during this period was a foam-padded dressing (Allevyn; Smith + Nephew) to relieve pressure on the wound. A wound pain specialist had recommended use of this dressing.

Protection of patient rights. The patient provided full consent to use the photographs and relevant clinical data in this study. The patient’s name and other identifying information were excluded from the manuscript and not disclosed to anyone other than the authors. The medical record was stored on NCT’s secure server and was not distributed via email or any other communication platform. All clinical information relevant to the study was viewed and extracted only with NCT’s secure server devices. The patient was provided with the manuscript for approval before submission. The patient was made aware of the authors’ interest in creating this report, and consent was obtained.

The authors reported the case of a patient with a long-standing PI that had been refractory to multiple previous therapies. The wound showed remarkable decrease in size and depth coinciding with a medical cannabis titration protocol. To the authors’ knowledge, this is the first reported case of orally administered medical cannabis oil potentially having a direct or indirect positive effect on wound healing.

Although it cannot be established that the medical cannabis regimen was the causal agent of wound healing, there is some evidence that it may have played either an indirect or direct role. Secondary data analysis from a previous longitudinal study of 247 patients with venous leg ulcers showed that tissue regeneration could be impaired in patients experiencing pain and lack of sleep.¹⁵ In the current study, the patient reported an amelioration in both these symptoms after using medical cannabis, indicating that medical cannabis may have stimulated wound healing indirectly by improving these symptoms. There is also some evidence that THC and CBD can modulate the inflammation response directly, which may be lead to wound healing effects.^2,3 A recent cell culture study reported that low-dose THC and CBD could prime the regenerative ability of stem cells, suggesting that systemically administered cannabinoids may have a direct effect on wound healing processes.¹⁶

Although the patient was using medical cannabis, she also began using a new type of bandage to dress the wound. This may be partly or wholly responsible for wound healing.

The conclusions that can be drawn from this report are limited because it describes a single case and cannot address causal relationships. In addition, detailed wound assessments were not available. Finally, the use of a foam dressing could have contributed to healing independently of the cannabis treatment regimen.

This case report provides an account of a patient who began using orally administered medical cannabis oil for sleep disturbances and pain management and subsequently experienced rapid healing of a chronic PI. Evidence for the wound-healing effects of cannabis is limited to theoretical preclinical work and a few open-label trials. It is unknown if the observed healing was indirectly or directly related to the cannabis treatment, and well-designed clinical trials are needed to examine these relationships and the safety and efficacy of medical cannabis for use in patients with chronic wounds.

Dr Diaz is research manager, Ms Katz is a BHSc candidate, Ms Langleben is a BHSc candidate, Mr Rabinovitch is a BSc candidate, and Dr Lewis is director, Neurology Centre of Toronto, Toronto, Canada. Address all correspondence to: Evan Cole Lewis, MD, Director, Neurology Centre of Toronto, 491 Eglinton Avenue West, Toronto, ON, M5N 1A8, Canada; email: evan.lewis@neurologycentretoronto.com.

None disclosed