There are generally 5 types of psoriasis: They are plaque, guttate, inverse, pustular and erythrodermic types. The most commonly recognized as plaque psoriasis. This is a skin condition and a disease. However, it is not contagious. The nomenclature is from Greek language which means "itching". It can be genetic or caused due to external influences, such as: allergic reaction to food or the atmosphere and also sometimes excess stress, smoking and drinking.

Once someone has psoriasis, he has a higher probability to have it for ever. The disease may vanish once, and might come back again. It might show good result to various kinds of treatments, and sometimes not at all. Basically psoriasis is a condition of the body over producing the skin cells. Some portion of the skin might get swelled up because of the presence of too many skin cells particularly in a single location. This might even become dry and flaky. It gives the sensation of itchy and red skin. It can turn out to be sore, cracked and even tender at times.

The body parts affected by Psoriasis are scalp, hands, and abdominal parts. Knees, feet and elbows are also affected subsequently. People can have dandruff problems and some times might lead to arthritis. It is a skin disorder guided by the immune system, involving a certain type of white blood cell i.e. T cell. Normally, it helps in protecting our body against various infections and diseases. In the case of this particulate disease, T cells are driven into action mistakenly and become very active, so that they develop other immune responses, which results in inflammation and rapid unstoppable growth of skin cells. In many it is found that, there is an old family history of this psoriasis.

Researchers studied a huge number of families attacked by psoriasis and recognized genes linked to this. People suffering from this may notice that there are periods when their skin goes worse, called flares, and then after that again improves. The cause of these flares includes infections, stress, smoking, much alcohol taking and also changes in climate that make the skin dry. Also, medicines, like beta-blockers, which are used for high blood pressure, and also lithium may enhance an outbreak or make the disease worse. Generally 30 percent of people affected by psoriasis also develop a kind of arthritis known as psoriatic arthritis, which causes stiffness, pain and inflammation in and around the joints of human body. This can develop at any age, but mostly appears between 30 and 50 years of age and harms men at a higher and quicker rate than women. Here also genes, immune system and environment play a role in the starting of the disease.

Early diagnosis and medication of this severe disease are required to relieve pain and swelling and help prevent further joint damage. But psoriasis sufferers are found firstly at the age of 15-20. Psoriasis Treatment is generally done in steps based on the severity of the disease, size of the areas involved, type of psoriasis, and the patient's response to initial treatments. This is generally called as the “1-2-3” approach. During step 1, medicine is applied to affected skin (topical treatment). In Step 2 light treatments (phototherapy) are used. Step 3 includes eating medicines or injection that cure the immune system (called systemic therapy).