Psoriasis is a relatively common autoimmune disease that causes red, peeling, dry skin and, in some cases, can lead to psoriatic arthritis. Studies have shown that cannabis can help treat psoriasis by regulating the immune system and managing skin cell hyperactivity. The disease causes them to accumulate on the surface, causing a thick reddish appearance that can appear anywhere on the body, being most common on the elbows, knees, back, face, scalp, palms and feet.

Psoriasis Overview

Psoriasis is caused by problems with the immune system. Cell renewal is a natural process where cells from the deeper layers of the skin rise to the surface. This process typically takes a month, but in a person with psoriasis it is much faster, taking just a few days. This condition is much more common in adults.

The appearance of psoriasis outbreaks varies between individuals. Some may experience redness and peeling, while others may have dry skin with cracks and bleeding, which can cause pain and itching. The severity of symptoms varies, with rashes lasting weeks or months. Infections, stress, dry skin, and some medications can make symptoms worse.

Psoriasis is likely caused by a type of white blood cell that mistakenly attacks healthy skin cells. These overactivated T cells also trigger immune responses, causing blood vessels in the skin to dilate. Genetics plays a role, but psoriasis can be caused by environmental factors such as infections, skin wounds, stress, cold weather, smoking, excessive alcohol consumption, and certain medications.

The disease can also cause swelling and stiffness in the joints and hardening of the nails, a condition called psoriatic arthritis. It occurs when the immune system begins to attack healthy cells and tissues, leading to joint inflammation and the overproduction of skin cells. Joints throughout the body can be affected, including the spine and fingers. Signs and symptoms may resemble those of rheumatoid arthritis. This condition can also cause pain in the feet and lower back, and swelling of the fingers and toes.

There is no cure for psoriasis, however, certain treatments can slow the growth of skin cells and offer relief. Medications such as topical corticosteroids and retinoids, vitamin D analogs, anthralin, calcineurin inhibitors, and salicylic acid can help manage inflammation, reduce peeling, and encourage skin shedding. Additionally, moisturizers and exposure to sunlight can help improve symptoms of the disease.

Discoveries about the effects of cannabis on Psoriasis

Studies indicate that the cannabinoids found in cannabis can help control psoriasis through their interaction with the endocannabinoid system (ECS), which, when impaired in any way, can lead to the development of autoimmune diseases such as psoriasis. However, research has shown that the interaction of cannabinoids with the cannabinoid receptors of the SEC helps regulate the normal functions of the immune system 2,5,12.

A previous clinical study found that cannabis helps prevent psoriasis flare-ups by activating the CB2 receptors of the endocannabinoid system 4. More recently, a review of the literature concluded that the anti-inflammatory and regulatory effects of cannabinoids on the immune system make them possible therapeutic agents for psoriasis 3.

Research further suggests that cannabis may help treat the symptoms of psoriasis by regulating the hyperactivity of T cells. One study found that the interaction of cannabinoids with ECS receptors is associated with several biological processes related to the skin, including the proliferation of its cells 1. A more recent study determined that CB receptors likely play a circumstantial role in T cell activity, but that cannabis’s ability to inhibit the activity of these cells is not related to the activation of CB receptors 13.

Four of the main cannabinoids found in cannabis, including THC (tetrahydrocannabinol), CBD (cannabidiol), CBN (cannabinol), and CBG (cannabigerol), have been shown to inhibit overactivated T cells and thus play a therapeutic role in the treatment of psoriasis 13. The anti-inflammatory properties of cannabinoids have also been implicated in the treatment of psoriasis 7. Additionally, studies have found that through the activation of receptors CB2 cannabinoids can help alleviate and, in some cases, reverse damage caused by skin inflammation 6.

Recent studies on the effects of cannabis on Psoriasis

• Due to the anti-inflammatory effects of cannabis, it may be an effective therapeutic agent for psoriasis. Cannabis for refractory psoriasis – hope for a new treatment and review of the literature. http://www.eurekaselect.com/142052/article
• The cannabinoids in cannabis prevent the overactivation of T cells, and thus help treat psoriasis. Cannabinoids inhibit the proliferation of keratinocytes in humans through a mechanism unrelated to CB1/CB2 receptors and offer a possible treatment for psoriasis.
  http://www.jdsjournal.com/article/S0923-1811(06)00315-X/fulltext
• Activation of CB2 receptors by cannabis helps prevent the exacerbation of skin diseases such as psoriasis. Pharmacological properties and therapeutic possibilities for drugs that act on endocannabinoid receptors.
  http://www.eurekaselect.com/90421/article

References:

1. Bíró, T., Tóth, B. I., Haskó, G., Paus, R., and Pacher, P. (2009). The endocannabinoid system of the skin in health and disease: novel perspectives and therapeutic opportunities. Trends in Pharmacological Sciences, 30(8), 411–420. Retrieved from
   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2757311/.
2. Croxford, J.L., and Yamamura, T. (2005, September). Cannabinoids and the immune system: potential for the treatment of inflammatory diseases? Journal of Neuroimmunology, 166(1-2), 3-18. Retrieved from
   http://www.jni-journal.com/article/S0165-5728(05)00160-8/fulltext.
3. Derakhshan, N., and Kazema, M. (2016, May 11). Cannabis for refractory psoriasis-high hopes for a novel treatment and a literature review. Current Clinical Pharmacology, [Epub ahead of print]. Retrieved from
   http://www.eurekaselect.com/142052/article.
4. Fowler, C.J. (2005, December). Pharmacological properties and therapeutic possibilities for drugs acting upon endocannabinoid receptors. Current Drug Targets: CNS and Neurological Disorders, 4(6), 685-96. Retrieved from
   http://www.eurekaselect.com/90421/article.
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6. Li, S.S., Wang, L.L., Liu, M., Jiang, S.K., Zhang, M., Tian, Z.L., Wang, M., Li, J.Y., Zhao, R., and Guan, D.W. (2016). Cannabinoid CB2 receptors are involved in the regulation of fibrogenesis during skin wound repair in mice. Molecular Medicine Reports, 13(4), 3441–3450. Retrieved from
   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4805070/.
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13. Wilkinson, J.D., and Williamson, E.M. (2007, February). Cannabinoids inhibit human keratinocyte proliferation through a non-CB1/CB2 mechanism and have a potential therapeutic value in the treatment of psoriasis. Journal of Dermatological Science, 45(2), 87-92. Retrieved from
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