Pruritus

Itching (pruritus) is a common symptom associated with numerous skin diseases, as well as a secondary symptom of numerous serious conditions such as renal failure and liver disease. Itching, unlike other skin sensations, is generally a result of CNS activities and typically goes untreated by standard medical therapies.

The endocannabinoid system is acknowledged to play an important role in maintaining skin health[1] and cannabinoids have been identified as promising agents for the treatment of acne[2], itch[3], epidermolysis bullosa[4-5], and other types of skin conditions[6-8].

Several small observational trials and case reports document beneficial effects of either cannabis or cannabinoids for patients with pruritis.

Writing in the August 2002 issue of the American Journal of Gastroentrology, investigators from the University of Miami Department of Medicine reported successful treatment of pruritus with 5 mg of THC in three patients with cholestatic liver disease.[9] Prior to cannabinoid therapy, subjects had failed to respond to standard medications and had lost their ability to work. Following evening cannabinoid administration, all three patients reported a decrease in pruritus, as well as “marked improvement” in sleep and were eventually able to return to work. Resolution of depression was also reported in two out of three subjects. “Delta-9-tetrahydrocannabinol may be an effective alternative in patients with intractable cholestatic pruritus,” investigators concluded.

The following year, British researchers reported in the journal Inflammation Research that the peripheral administration of the synthetic cannabinoid agonist HU-211 significantly reduced experimentally-induced itch in 12 subjects.[10] Investigators had previously reported that topical application of HU-210 on human skin reduced experimentally-induced pain and acute burning sensations.[11]

Polish researchers in 2015 reported that application of an endocannabinoid-based topical cream reduced uremic pruritus and xerosis (abnormal dryness of the skin) in hemodialysis patients.[12] Three weeks of twice-daily application of the cream “completely eliminated” pruritus in 38 percent of trial subjects and “significantly reduced” itching in others. Eighty-one percent of patients reported a “complete reduction” in xerosis following cannabinoid therapy.

Most recently, a team of John Hopkins University researchers reported in 2021 about the successful use of cannabis by a woman in her 60s with a 10-year history of pruritis. The subject had been unresponsive multiple anti-prurtic therapies, including topical corticosteroids. Writing in JAMA Dermatology, researchers reported that the patient experienced sustained improvements over a 20-month period following her use of botanical cannabis and cannabis-based tinctures. The subject’s Dermatology Life Quality Index Score fell from 17 to 1 over the study period. The subject also reported ceasing her intake of other anti-prurtic medications. Minimal adverse effects were reported[13]

As a result of this and other data[14-15], some dermatology experts have opined that cannabinoids may represent “promising new avenues for managing itch more effectively”[16] and that the use of cannabinoids may be a viable option for patients.[17]

REFERENCES

[1] Trusler et al. 2017. The endocannabinoid system and its role in eczematous dermatoses. Dermatitis 28: 22-32.

[2] Phillip Cohen. 2021. Therapeutic and cosmetic uses of cannabis: Cannabinoids for acne treatment and skin rejuvenation. Skinmed 19: 45-47.

[3] Science News. “Cannabinoids may soothe certain skin diseases, say researchers,” April 18, 2017.

[4] Schrader et al. 2019. Combined tetrahydrocannabinol and cannabidiol to treat pain in epidermolysis bullosa: A report of three cases. The British Journal of Dermatology 180: 922-924.

[5] Chelliah et al. 2018. Self-initiated use of topical cannabidiol oil for epidermolysis bullosa. Pediatric Dermatology 35: 224-227.

[6] Baswan et al., 2020. Therapeutic potential of cannabidiol for skin health and disorders. Clinical, Cosmetic and Investigational Dermatology 13: 927-942.

[7] Nickles and Lio. 2020. Cannabinoids in dermatology: Hope or hype? Cannabis and Cannabinoid Research [E-pub ahead of print]

[8] Eagleston et al. 2018. Cannabinoids in dermatology: A scoping review. Dermatology Online Journal [online access journal].

[9] Neff et al. 2002. Preliminary observation with dronabinol in patients with intractable pruritus secondary to cholestatic liver disease. American Journal of Gastroenterology 97: 2117-2119.

[10] Dvorak et al. 2003. Histamine induced responses are attenuated by a cannabinoid receptor agonist in human skin (PDF). Inflammation Research 25: 238-245.

[11] Dvorak et al. 2003. Cannabinoid agonists attenuate capsaicin-induced responses in human skin. Pain 102: 283-288.

[12] Szepietowski et al. 2005. Efficacy and tolerance of the cream containing structured physiological lipid endocannabinoids in the treatment of uremic pruritus: a preliminary study. Acta Dermatovenerologic Croatica (Croatia) 13: 97-103.

[13] Roh et al., 2021. Treatment of chronic pruritis with medical marijuana. JAMA Dermatology [E-pub ahead of print].

[14] Sheriff et al. 2020. The potential role of cannabinoids in dermatology. The Journal of Dermatological Treatment 31: 839-845.

[15] Samaha et al. 2020. Cannabis use for restless legs syndrome and uremic pruritis in patients with maintenance dialysis: A survey. Canadian Journal of Kidney Health and Disease [E-pub ahead of print]

[16] Paus et al. 2006. Frontiers in pruritus research: scratching the brain for more effective itch therapy. Journal of Clinical Investigation 116: 1174-1185.

[17] Mounessa et al. 2017. The role of cannabinoids in dermatology. Journal of the American Academy of Dermatology 77: 188-190. >