Psoriasishttps://en.wikipedia.org/wiki/Psoriasis
Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by raised areas of abnormal skin. These areas are red, or purple on some people with darker skin, dry, itchy, and scaly. Injury to the skin can trigger psoriatic skin changes at that spot, which is known as the "Koebner phenomenon".

Various treatments can help control the symptoms. These treatments include steroid creams, vitamin D3 cream, ultraviolet light, and immunosuppressive drugs, such as methotrexate. About 75% of skin involvement improves with creams alone. Various biological immunologic agents are being developed for the treatment of psoriasis.

Psoriasis is a common disorder and the disease affects 2-4% of the population. Men and women are affected with equal frequency. The disease may begin at any age, but typically starts in adulthood. Psoriatic arthritis affects up to 30% of individuals with psoriasis.

○ Treatment ― OTC Drugs
Sunlight can help psoriasis because sun exposure induces immunological changes in patients with psoriasis. Mild hydrocortisone ointment may help to treat some small lesions of psoriasis.
#OTC steroid ointment

○ Treatment
Psoriasis is a chronic disease and a lot of treatment agents are being studied. Biologics are the most effective but very expensive.
#High potency steroid ointment
#Calcipotriol cream
#Phototherapy
#Biologics (e.g. infliximab, adalimumab, secukinumab, ustekinumab)
  • Back and arms of a person with psoriasis
  • Typical psoriasis
  • Guttate Psoriasis; It often occurs after symptoms of a cold.
  • Guttate Psoriasis
  • A thick scaly plaque with erythema is a typical manifestation of psoriasis.
  • Psoriasis on the palms. If it occurs on the palms of the hands, blisters may form.
  • Severe 'pustular psoriasis'.
  • Guttate Psoriasis
References Psoriasis 28846344 
NIH
 Phototherapy 33085287 
NIH
 Tumor Necrosis Factor Inhibitors 29494032 
NIH
Tumor necrosis factor (TNF)-alpha inhibitors, including etanercept (E), infliximab (I), adalimumab (A), certolizumab pegol (C), and golimumab (G), are biologic agents which are FDA-approved to treat ankylosing spondylitis (E, I, A, C, and G), Crohn disease (I, A and C), hidradenitis suppurativa (A), juvenile idiopathic arthritis (A), plaque psoriasis (E, I and A), polyarticular juvenile idiopathic arthritis (E), psoriatic arthritis (E, I, A, C, and G), rheumatoid arthritis (E, I, A, C, and G), ulcerative colitis (I, A and G), and uveitis (A).