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About Psoriasis

In this section, you or a loved one can find out more about medical treatments, research studies and practical information about psoriasis. Read on to find answers to some of your questions as well as links to other information. Being informed is an important first step towards becoming an active decision-maker in your care plan.

What Is Psoriasis?

Psoriasis is a disease that causes the skin cells to grow too quickly. Rough, dry and thick patches of dead skin called lesions or plaques appear on the skin. The lesions can appear red and irritated with silvery scales and a distinct border between the plaque and normal skin. Sometimes the lesions itch, burn or bleed. Plaques are most often seen on the elbows, knees and torso, but can appear anywhere, including the scalp. Fingernails and toenails can also be affected. The nails can become discoloured, thickened, lift up from the skin and even become “pitted” as small holes form in them.

Scientists do not yet know the precise cause of psoriasis or how to cure it. But scientists do know about the types of psoriasis symptoms, how to treat the symptoms and how the disease progresses.

Unfortunately, psoriasis is a chronic disease, meaning that once it starts, it is likely to persist for the rest of your life.

What Causes Psoriasis?

The lesions you see on your skin are the result of an overactive immune system, which mistakenly attacks your own healthy skin cells. So, psoriasis is an “autoimmune disease”. In fact, psoriasis is the most common autoimmune disease. Scientists are not sure why this happens. But, psoriasis is not contagious — you or your loved ones cannot catch it from someone who has it. Someone who smokes, is overweight or has a relative with psoriasis is also at higher risk of developing the disease.

Scientists are studying the potential causes and progression of psoriasis:

There are some important factors about psoriasis and the disease progression that are known:

  • Genetics: Some people have genes that set them up to develop psoriasis.
  • Triggering event: Some external factors are usually needed to start psoriasis. Triggers are not the same for every patient, but there are some that are common to many people with psoriasis. Among them:
    • Stress
    • Damage or injury to the skin, like scratches, scrapes, insect bites, cuts, sunburns
    • Use of certain medications
    • Certain infections
    • Smoking
    • Heavy alcohol consumption
    • Cold weather
What Are the Effects of Psoriasis?

Inflammation is a natural process that your body normally uses to protect itself from harm. When a portion of skin is affected, it becomes red, swollen and painful, and feels hot or warm to the touch: this is called inflammation.

A normal skin cell forms at the bottom layer of your skin and slowly makes its way to the surface as more new skin cells form underneath it. The skin cell reaches the surface and eventually falls off without you noticing. A normal skin cell lasts 28 to 30 days. In psoriasis, however, when your immune system malfunctions and produces inflammation in an area of your skin, it only takes three to four days for new skin cells to mature and reach the surface. The old skin cells do not have time to fall off and build up with other skin cells instead, creating inflamed skin scales and skin plaques.

The severity of psoriasis is measured by how much skin is covered by lesions or plaques. The body surface area or BSA is the percentage of your skin surface area affected by plaques. The size of your palm is usually 1% of the total body surface and acts as the reference point. The severity classifications are:

  • Mild psoriasis: less than 10% BSA
  • Moderate psoriasis: 10% to 20% BSA
  • Severe psoriasis: more than 20% BSA

Severity can also be measured by how psoriasis affects your quality of life. For example, even a mild case affecting only a small area on the scalp or the palms or soles of the feet can have a significant impact on your life.

Psoriasis symptoms tend to change over time, appearing differently in each person. People with psoriasis often suffer from a cycle with periods of active disease that are called flare-ups, followed by periods when symptoms disappear that are called remissions. The triggers, which can set off psoriasis in the first place, often worsen symptoms or cause a flare-up after a period of remission.

If inflammation from psoriasis is left untreated, it can eventually lead to thickened skin, scarring, disfigurement and bacterial skin infections caused by scratching and touching plaques. Fortunately, there are many ways to treat psoriasis and prevent complications before they happen.

Where Do Plaques Form?

Psoriasis plaques can appear anywhere on the body. Plaques can range from a few pinhead-sized spots to major eruptions that cover large areas of the body.

Are There Other Complications?

If you have psoriasis, you are at greater risk of developing other diseases, such as:

  • Psoriatic arthritis (in about 40% of people with psoriasis)
  • Depression (in about a third of people with psoriasis)
  • Anxiety
  • Crohn's disease (a type of inflammatory bowel disease)
  • Diabetes
  • Hypertension (high blood pressure)
  • Cardiovascular disease

Many psoriasis patients also feel embarrassed by their appearance, avoiding social situations or other daily activities, and intimacy with their partners.

Lifestyle Options

For most people, regardless of having psoriasis or not, exercise, healthy eating, good sleeping habits, soothing skin care routines and relaxation techniques are recommended. A healthy lifestyle can lead to an enhanced quality of life for most people. Talk to your doctor before making any lifestyle changes. 

  • Care for your skin: Proper skincare will help you to manage some psoriasis symptoms.
  • Soak up a little sun: Moderate exposure to sunlight usually helps by slowing the growth of skin cells. However, too much sun damages your skin, so always use sunscreen. Be aware that in rare cases, ultraviolet (UV) light exposure makes some types of psoriasis worse.
  • Control air humidity: Use a humidifier to reduce exposure to drier air, which can aggravate psoriasis, especially in winter.
  • Moisturise your skin: Keep your skin moist with topical creams and lotions that contain cocoa butter, lanolin, petroleum jelly, light mineral oil or baby oil.
  • Avoid irritating products: Do not use strong soaps and moisturisers that contain perfumes or chemicals.
  • Take daily baths: Gently washing your skin every day helps to remove dead skin and calm inflammation.
  • Use medicated creams and ointments: Your pharmacy has over the counter (OTCs) products that can help reduce itching and scaling. For scalp psoriasis, try a medicated shampoo. Always follow label directions and your doctor's advice.
If you have psoriasis, exercise and watch what you eat to maintain a healthy weight. Maintaining a healthy weight helps to reduce the severity of your psoriasis and can minimise your risk of developing related conditions like diabetes and heart disease.

First identify the triggers that bring about your flare-ups or make your symptoms worse. Then try to avoid them. For example:

  • Stay healthy: Try to make an effort to prevent infections 
  • Avoid alcohol: A suspected trigger, alcohol may decrease the effectiveness of some psoriasis treatments
  • Avoid tobacco products: Choose not to smoke
  • Avoid or reduce Stress: Keep away from unnecessary stressful situations
  • Opt out of risky activities: Avoid situations that could injure your skin
  • Avoid triggering foods: Keep a food diary and review it regularly to see which foods may be acting as triggers –while science hasn't proven that certain foods either improve or aggravate psoriasis, it is believed that certain foods can aggravate symptoms of the disease
  • Avoid too much sun: staying in the sun for prolonged periods can cause sunburn
Stress can lead to an increase in blood pressure, interrupt sleep, and play a role in the intensity of psoriasis symptoms. It is important to first identify stress triggers and then develop relaxation and coping skills to decrease these triggers. This can help improve your overall well-being while giving you a greater sense of control over your psoriasis.

On days when you might feel particularly self-conscious about the appearance of your skin, you can cover the affected areas with clothing, or use make-up or concealer to mask redness and plaques.

However, never cover open sores or unhealed lesions; make-up, concealer and even clothing may irritate the skin even more.

Complementary Therapy Options

For some people with psoriasis, treatments that fall outside the scope of traditional western medicine can sometimes work very well for symptom relief. Ask your doctor about alternative therapies.

Omega-3 fatty acids (fish oil) supplements may reduce inflammation associated with psoriasis. Vitamin E is also thought to benefit skin and nails. Talk to your doctor for more guidance.
Some people add natural relief therapies to their medical psoriasis treatments, such as acupuncture, acupressure, massage therapy or biofeedback (with or without hypnosis). Always discuss these alternative treatment options with your doctors, and make sure that you tell any alternative health specialist about your condition and medications in order to avoid injury.
Medical Treatments

The goals of medical treatment for psoriasis are:

  • Relieve symptoms
  • Relieve inflammation
  • Interrupt the cycle of increased production of skin cells

Your doctor can explain the different medications, their benefits and side effects. It is likely that you will try different therapies or combinations before finding the best prolonged symptom relief.

Topical corticosteroids (i.e. the kind of steroid applied directly to the skin) are the most frequently prescribed for treating mild-to-moderate psoriasis. Topical corticosteroids in a cream or lotion are applied directly onto the plaques or lesions. They slow cell turnover, which reduces inflammation and relieves itching. They should only be used for limited periods of time, because long-term use or overuse of strong corticosteroids can cause thinning of the skin and resistance to the treatment's benefits.
Brief exposure to small amounts of sunlight, or to controlled doses of ultraviolet B (UVB) light from an artificial source, may improve mild-to-moderate psoriasis symptoms. During UVB treatment, psoriasis may worsen temporarily before improving. Light therapy can cause short-term side effects such as redness, itching and dry skin. Applying moisturisers to the affected areas helps lessen these side effects. Combining UVB light exposure with other therapies may increase efficacy dramatically and allow for lower doses of medication.
If your psoriasis is severe and does not respond to other treatments, your doctor may recommend using a drug from the retinoid family. It is not known exactly how retinoids work, but they reduce skin cell production and the speed at which skin cells grow and shed. Symptoms of psoriasis usually return once the retinoid therapy is stopped. Common side effects of taking retinoids are dry skin and mucous membranes, itching and hair loss. Women must avoid pregnancy for at least three years after taking retinoids since they can cause severe birth defects.
Disease-modifying anti-rheumatic drugs (DMARDs) are medications often prescribed to relieve skin inflammation and decrease skin cell production in people with moderate-to-severe psoriasis in addition to their traditional application as a treatment for rheumatic diseases. DMARDs can take time to work – it may be weeks or months before you see a noticeable difference in your symptoms. During this time, your doctor may prescribe another medication, like a topical corticosteroid, to help control symptoms. Common side effects of taking DMARDS include nausea, diarrhoea, upset stomach, dizziness, increased risk of infection and liver problems. Regular blood tests are needed for the monitoring of blood cell counts and liver function.

Biologic response modifiers, or “biologics” for short, are medications (given by injection) specifically designed to target your body’s immune system. Like Disease-modifying anti-rheumatic drugs (DMARDs), biologics are used to slow the production of skin cells, and ease the pain and swelling of psoriasis plaques and scales.

Biologics can take some time to work. Some people notice the effects of the medication quickly (within a week), while other patients may take months to feel the effects. They are also prescribed when other psoriasis therapies are not effective, and in people with moderate-to-severe cases. Common side effects with biologics include mild skin reactions at the injection site, nausea, abdominal pain and headaches. Rarely, people who take biologics may develop serious infections, lupus-like reactions, nervous system diseases and cancer. You should not take a biologic if you are pregnant or breastfeeding, or have a history of multiple sclerosis or cancer. Inform your doctor if you have a history of tuberculosis, hepatitis B or recurrent infections.


Please note that the information on this website is intended for informational purposes only and should not be used as a substitute for seeking medical advice or treatment from a healthcare professional. You should not use this information to diagnose or treat a medical condition or health problem. Speak to a healthcare professional if you have any questions about your health, medical condition, symptoms or treatment options.


A leading national charity and membership organisation for people affected by psoriasis in the UK

The National Psoriasis Foundation (NPF)is a non-profit, voluntary health agency in the USA dedicated to finding a cure for psoriasis and psoriatic arthritis and eliminating their devastating effects through research, advocacy and education.


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