- Psoriasis is a long-term inflammatory disease that causes red, scaly skin lesions (sores).
- For some people, psoriasis also affects their nails and joints.
- Your doctor will usually diagnose psoriasis by asking you some questions and examining your skin.
- There is no cure for psoriasis but there are many treatments that can help to keep it under control.
What is psoriasis?
Psoriasis is a long-term inflammatory disease that affects the skin. Psoriasis will typically look like thick silvery scales, and can be dry, itchy and often painful. Psoriasis can occur on any part of the body, including the scalp, hands, feet, finger or toes nails and genitals.
Psoriasis tends to come and go over time. About 1 in every 2 people with psoriasis have changes in their nails, such as pitted, discoloured or crumbly nails.
What are the different types of psoriasis?
There are many different types of psoriasis.
Plaque psoriasis is the most common type of psoriasis, occurring in 9 out of 10 people with psoriasis. It is usually involves red, thick, sharply edged lesions (sores). These lesions can occur anywhere on the body but usually affect the elbows, knees, lower back and scalp (the skin on the head).
Other less common types of psoriasis include:
Inverse (flexural) psoriasis occurs in areas where skin rubs against skin like the armpits, groin, between the buttocks, the ears and belly button. Lesions are sharp edged patches with little or no scale.
Palmo-planter psoriasis occurs on the palms of the hands and the soles of the feet. The skin looks scaley, red and like plaques found on other parts of the body.
Guttate psoriasis occurs in young adults, usually 2 to 3 weeks after a viral infection or tonsilitis. It causes small, tear-drop shaped lesions. This is usually widespread across the torso, back and limbs
Pustular psoriasis has raised bumps (yellow-white blisters) filled with non-infectious pus (pustules) on tender red skin. You will need to go to the hospital and get oral medicines to treat this condition.
Erythrodermic psoriasis has red, inflamed areas of psoriasis involving all of the skin. It usually happens in people who have previously had stable plaque psoriasis.
What are the symptoms of psoriasis?
Psoriasis causes different symptoms in different people. Psoriasis can develop at any point in your lifetime. Symptoms usually begin in young adulthood, and 3 out of 4 people with psoriasis usually develop it before the age of 45 years.
The most common symptoms of plaque psoriasis are dry, raised, red patches of skin (plaques) covered with silvery scales. The patches usually appear on your knees, elbow, lower back, and scalp, but they can appear anywhere on the body. Psoriasis can also cause dents and discolouration of your nails.
Cross section illustration of psoriasis
Close-up of psoriasis on skin
What causes psoriasis?
Although the cause of psoriasis is unknown, it is thought that it occurs in people who have a genetic tendency for their skin's immune system to react to certain triggers. These may include infections such as streptococcal tonsillitis, HIV and other viral infections, or by severe stress.
If you have a family member with psoriasis, you are also more likely to develop it.
Some medicines may trigger psoriasis or cause your psoriasis to become more severe. These medicines include lithium, beta-blockers, and anti-malarial medicines. If you have psoriasis, you need to be extra careful if you are taking corticosteroid medicines — ask your doctor how you can slowly reduce your dose over time to prevent a flare-up of your psoriasis.
Your guide to psoriasis - video
When should I see my doctor?
If you develop red, scaly, raised patches on your skin that don't go away on their own, you should see your doctor.
If you already have a diagnosis of psoriasis, you should also see your doctor if your condition:
- becomes severe or widespread
- causes you discomfort or pain
- causes you concern about the appearance of your skin
- doesn't improve with treatment
- develop painful swollen and stiff joints
How is psoriasis diagnosed?
If you think you have psoriasis, see your doctor. They will ask you some questions on your condition, and may ask about your family's medical history. Your doctor will examine your affected skin. They may refer you to a dermatologist, or a rheumatologist if your joints are affected. Sometimes, they will take a biopsy, or refer you to another doctor to take a biopsy, to confirm the diagnosis.
How is psoriasis treated?
There is no cure for psoriasis but there are many psoriasis treatments that can help to keep it under control and reduce flare-ups. If you have psoriasis, you may need lifelong treatment to help manage the condition.
There are 3 approaches to treating psoriasis: treatments you apply on your skin, light therapy and systemic (whole body) treatments.
Topical treatments you apply on your skin as a cream or paste:
- corticosteroid medicines
- calcipotriol (a form of vitamin D)
- tazarotene (in a class of medicines called retinoids)
- coal tar
Light therapy options include ultraviolet (UV) phototherapy and photochemotherapy
Systemic (whole body) treatments may include one or more of the following:
- biological medicines (from natural sources such as microorganisms, plants, animals and humans)
There are also more general things you can do to help control your psoriasis. These measures include:
- moisturising your skin daily — ask your doctor to recommend a suitable moisturiser
- taking your prescribed treatment exactly as prescribed to help prevent flare-ups
- reducing stress
- having a healthy lifestyle and eating a healthy diet
- quitting smoking and limiting how much alcohol you drink
Can psoriasis be prevented?
Unfortunately, psoriasis can't be prevented. You can help reduce your chance of a flare-up of by taking the medicines that your doctor prescribes regularly.
Complications of psoriasis
Psoriatic arthritis is an inflammatory arthritis associated with psoriasis. It affects joints as well as areas where tendons connect with bone causing stiffness, pain, swelling and sometimes damage to the affected joints. About 1 in 4 people with psoriasis will develop psoriatic arthritis.
Psoriasis can also seriously affect your emotional and social wellbeing. People with psoriasis are more likely to have mental health problems, including depression. Psoriasis may affect your ability to work, go to school or participate in physical activities.
Resources and support
For more information about the symptoms, diagnosis and treatment of psoriasis, see the following websites:
Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.
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Last reviewed: June 2023