Psoriasis - Causes, Risk Factors And Symptoms


Psoriasis is a skin disease that causes itchy, red scaly patches, mostly on the elbows, knees, scalp, and trunk.

Psoriasis is a common, long-term (chronic) disease. To help you manage the symptoms, treatments are available. To help you live better with psoriasis, you can incorporate coping strategies and lifestyle habits.


Common signs and symptoms include:

  • Silvery, thick scales on red patches of skin
  • Small scale removal spots (commonly seen in children)
  • Dry, cracked skin that may bleed or itch
  • Itching, burning or pain
  • Thickened, pitted or ridged nails
  • Swollen and stiff joints

Psoriasis plaques can range from a few dandruff-like scaly patches to major rashes that cover large areas. The most commonly affected parts are the elbows, face, knees, legs, lower back, palms, scalp, and soles.

There are several types of psoriasis, including:

  • Plaque psoriasis. Plaque psoriasis is the most common form which causes dry, raised, red patches of skin (lesions) covered with silvery scales. The plaques can be itchy or tender, and there may be a few or a lot of them. They usually appear on the elbows, knees, lower back, and scalp.
  • Psoriasis of the nails. The fingernails and toenails are affected by psoriasis, causing abnormal nail growth, discoloration and pitting. Psoriatic nails can loosen and separate from the nail bed (onycholysis). Severe cases can cause the nail to break down.
  • Guttate psoriasis. This type mainly affects young adults and children. It is usually triggered by an infection caused by bacteria such as strep throat. It is marked by small, scaly, drop-shaped lesions on the trunk, arms, or legs.
  • Reverse psoriasis. It mainly affects the skin folds in the groin, buttocks and breasts. Reverse psoriasis causes smooth patches of red skin that get worse with friction and sweating. Fungal infections can trigger this type of psoriasis.
  • Pustular psoriasis. This rare form of psoriasis causes clearly defined pus-filled lesions that occur in extensive plaques (generalized pustular psoriasis) or in smaller areas on the palms of the hands or the soles of the feet.
  • Erythrodermic psoriasis. The less common type of psoriasis is erythrodermic psoriasis which can cover your whole body with a peeling, red rash.
  • Psoriatic arthritis. Psoriatic arthritis causes swollen and painful joints that are typical of arthritis. Sometimes the first or only symptom or sign of psoriasis are joint symptoms. And sometimes only nail changes are visible. This can lead to stiffness and progressive joint damage which in more severe cases can lead to permanent joint damage.

When to see a doctor

Talk to your doctor also if your psoriasis:

  • Becomes severe or generalized
  • Causes you discomfort and pain
  • Worried about the appearance of your skin
  • Causes joint problems, such as pain, swelling, or inability to perform daily tasks\
  • Does not improve with treatment

The causes

Psoriasis can be an immune system problem that causes the regeneration of skin faster than normal. Plaque psoriasis is the most common type of psoriasis in which there is rapid turnover of cells resulting in plaques and red scales.

The cause of immune system malfunction is not entirely clear. Researchers believe environmental factors and genetics play a role. The condition is not contagious.

Psoriasis triggers

Many people predisposed to psoriasis may have no symptoms for years until the condition is triggered by an environmental factor. Common triggers for psoriasis include:

  • Infections, such as strep throat or skin infections
  • Weather conditions, particularly cold and dry
  • Skin injury, such as a cut or scrape, an insect bite, or severe sunburn
  • Stress
  • Smoking and exposure to second-hand smoke
  • Heavy alcohol consumption
  • Certain medications – including lithium, high blood pressure medications, and antimalarials
  • Rapid discontinuation of oral or systemic corticosteroids

Risk factors

Anyone can develop psoriasis. About a third of cases start in the pediatric years. These factors can increase your risk:

  • Family story. The condition runs in families. Your risk of getting the psoriasis increases if your parents are having it.
  • Stress. Because stress impact your immune system, high stress levels can increase your psoriasis risk.
  • Smoking. Smoking tobacco not only increases your risk for psoriasis, it can also increase the severity of the disease. Smoking can also play a role in the initial development of the disease.


If you have psoriasis, you are more at risk of developing other conditions, including:

  • Eye disorders, such as conjunctivitis, blepharitis and uveitis
  • Obesity
  • Type 2 diabetes
  • Arterial hypertension
  • Heart disease
  • Other autoimmune diseases, such as celiac disease, sclerosis, and inflammatory bowel disease called Crohn’s disease
  • Mental health issues like depression and low self-esteem