Psoriasis | Types, Diagnosis, Complications & Treatment

What Causes Psoriasis? What Triggers Psoriatic Lesions to Flare-up?

Although we don’t know for sure what causes psoriasis, our knowledge of its pathogenesis (how to work) is increasing. The most approved theory that explains the over-proliferation of the epidermal cells is the over-active immune response resulting from a triggering event. Dermatologists noticed some precipitating factors and events that usually precede the attacks of psoriasis. For some reason, these events trigger abnormal immune reactions.

These precipitating factors include:

1) Skin trauma is a common triggering factor for psoriasis. Psoriasis may be triggered by skin trauma or another disruption to the skin, contribute to the development of psoriasis or worsen pre-existing psoriasis. The integrity of both the epidermal and dermal layers of the skin must be disrupted by skin trauma or another injury. A wound, cut, laceration, gunshot wound, or skin abrasion are all considered different forms of skin trauma.
Skin trauma does not only mean physical injury but also chemical, thermal, and electrical injuries. Trauma may contribute to spreading psoriasis to healthy skin. The Koebner phenomenon, or the emergence of skin lesions of the same type of pre-existing disease, requires a substantial skin injury or other disruption to the epidermis to occur. Trauma-induced psoriatic lesions may take weeks to develop.

2) Some medications may cause or exacerbate psoriasis. Even though drug-induced aggravation may occur up to many months after the medication is initially administered, there is no way to find out whether this medication will induce psoriasis or not before taking it. Medication-induced psoriasis may persist or resolve spontaneously when the treatment is stopped.
Drugs may also cause brief exacerbations or flare-ups so make sure to inform your doctor about your medication. Drugs that may induce psoriasis include beta-blockers (hypertension medication), lithium, and ant-malarial drugs such as hydroxychloroquine. Although the topical steroid is used in the treatment of psoriasis, sudden withdrawal of steroids may induce an attack.

3) Stress and anxiety don’t induce psoriasis, but they worsen the condition of the psoriatic patients. Depressive disorders may contribute to an exacerbation of psoriasis and induction of acute attacks. In case of the presence of a psychological disorder, it should be treated simultaneously with psoriasis.

4) Sore throat caused by streptococcal infection may trigger the development and aggravation of guttate psoriasis. Streptococcal infections of other parts other than the throat aren’t reported to induce psoriasis. Guttate psoriasis may resolve spontaneously within weeks after treatment of the sore throat.

5) Decreased exposure to sunlight is believed to increase the susceptibility to developing psoriasis. Frequent exposure to sunlight maintains the vitality of the skin and keeps it healthy. Ultraviolet rays of the sun reduce the severity of psoriasis by slowing down the proliferation (growth) rate of the epidermal cells.