What is psoriasis?

Psoriasis is a common inherited inflammatory condition that can affects approximately 2.5% of the Australian population. It can affect both women and men and appear at any age.  Psoriasis mainly affects the skin; but recent studies have indicated that psoriasis may affect other parts of the body or organs.  There is no cure for psoriasis, however it can be effectively treated and managed.

The severity of psoriasis varies widely between people. For most people, it will be mild and require occasional treatment, often only needing topical applications, while others may have severe disease requiring regular treatment. The appearance and severity of an individual’s symptoms will also vary over time.

Around one third of people with psoriasis also develop psoriatic arthritis, a related disease which causes inflammation of the joints. Psoriatic arthritis is usually treated by a rheumatologist who works closely with a dermatologist or general practitioner (GP).

Many people find the appearance of psoriasis embarrassing and this can have a significant impact on their mental health; rates of anxiety and depression are higher in people with psoriasis than the general population.

Psoriasis is more frequently associated with other health conditions that form part of the metabolic syndrome including diabetes, obesity, high cholesterol, and high blood pressure.


Signs and symptoms

Psoriasis causes skin cells to grow rapidly and build up on the surface of the skin. This gives the appearance of red, thick, scaly, dry, itchy patches (plaques) that can be painful. The skin signs of psoriasis can look similar to other skin conditions, so it is important you receive the correct diagnosis. Common signs and symptoms of psoriasis include:

  • raised, red, inflamed lesions covered in silvery scales (plaques)
  • small, red, individual spots, which can be flat or raised 
  • dry skin that may crack and bleed
  • itching, burning, or soreness of the skin
  • thickened, pitted nails or separation of the nail from the nail bed
  • swollen, stiff joints.

There are different types of psoriasis that may cause different symptoms. The most common types of psoriasis, include:

Plaque psoriasis: Most common type of psoriasis. The affected areas of the skin appear as thick, raised scaly patches. 

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Image appears with permission from the Skin Health Institute

Guttate psoriasisMore commonly seen in children, adolescents and young adults, typically following a throat infection known as Streptococci. Guttate psoriasis causes widespread small red spots, commonly on the trunk, arms and thighs.

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Image appears with permission from Getpsorted

Pustular psoriasisThis type of psoriasis is uncommon and mostly occurs in adults, particularly smokers. Pustular psoriasis causes small pustular 'blisters', surrounded by red skin.

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Image appears with permission from the Skin Health Institute


Palmoplantar psoriasis: Palmoplantar psoriasis affects the soles of the feet and palms of the hands. Thickened, red, scaly patches of skin appear and develop  painful cracked skin.

Inverse psoriasis: Typically appears as red, smooth patches in the folds of the skin (e.g. armpits, groin, under the breasts and between the buttocks).

Erythrodermic: This is a severe form of psoriasis that affects most of the skin with widespread redness. It is a rare form of psoriasis but is considered a medical emergency and requires prompt treatment


What causes psoriasis?

The exact cause of psoriasis is unknown. Psoriasis runs in families (30% of patients have a positive family history) and is thought to be due to a combination of genetic and environmental factors. An overactive immune system is known to play an important role in driving the disease and many treatments work by suppressing different parts of the immune system.

Psoriasis is not contagious. It is not caused by dirty skin or poor hygiene.

While we do not know the cause of psoriasis, we do know there are several “triggers” that may make psoriasis worse:

  • Stress can cause psoriasis to flare up for the first time or can aggravate existing psoriasis.
  • Damage (trauma) to the skin can cause psoriasis to appear in these areas). Examples include sunburn, cuts, and scratches.
  • Medications can worsen psoriasis including lithium, antimalarial drugs, some anti-inflammatory drugs, certain heart medications (‘beta-blockers’), and some blood pressure medications.
  • Infections by bacteria and certain viruses can trigger psoriasis for the first time or aggravate existing disease.
  • Changes in hormones, such as in pregnancy, can cause changes in psoriasis severity.
  • Smoking increases the risk of developing psoriasis and the severity of the disease. 


How is it diagnosed? 

Only a healthcare professional can diagnose psoriasis. In most people, a diagnosis of psoriasis can be made based on how the rash looks.

A skin biopsy is rarely needed. Investigations may be needed to rule out other conditions (e.g., skin scrapings for fungal infections), or may be performed prior to instituting treatment (e.g., blood tests).

Your doctor may use the Psoriasis Area and Severity Index (PASI) and the Dermatology Life Quality index (DLQI) to assess the extent and severity of psoriasis and its impact. For more information, please visit


What will happen to me?

Psoriasis can affect people in different ways. Some people will find they only have minimal psoriasis plaques that can be treated with topical applications (creams, lotions, ointments etc.). Others may have severe psoriasis that affects multiple parts of their body, (e.g., scalp, trunk and nails) and require stronger medications or ultraviolet light treatment)  The good news is that psoriasis can be treated, and your symptoms can improve.

Psoriasis may affect your mood. It is common for some people with psoriasis to feel depressed, anxious and embarrassed. It might affect the type of clothes you can wear and your ability to do daily activities. This can all add to feelings of stress, anxiety and depression, which can trigger a psoriasis ‘flare’. Treating your psoriasis and improving both the appearance of the skin and your symptoms can help to improve negative emotions. Speaking to your doctor about your feelings, and how to manage them, can also improve your psoriasis. It is important you speak to your doctor if you experience any other symptoms, such as joint pain, which may be a sign of psoriatic arthritis. By treating your psoriasis and maintaining your general health you can reduce the risk of developing other health conditions associated with psoriasis.


Is there a cure for psoriasis?

There is no cure for psoriasis, which means that there are no treatments that will make it go away forever. However, there are many treatments that are highly effective, and most patients can achieve ‘normal-looking’ skin. Psoriasis does not scar but can leave post-inflammatory pigmentation (darker patches of skin).



There are a variety of treatments for psoriasis which come in different forms. A GP or dermatologist will recommend the treatment that is best for you.

Treatment of psoriasis starts with avoiding the triggers (mentioned above) that can make it worse.

Read our Treatments for psoriasis article for more information on the types of psoriasis treatments. 


What can I do?

There are several things you can do to help treat and manage your psoriasis to ensure you live a full and happy life.

  • Speak to your doctor to get the right diagnosis and treatment to help manage your condition
  • Maintain a healthy weight by exercising regularly, eating a healthy diet and moderating your alcohol intake
  • Don’t smoke, as this may worsen your psoriasis. If you do, speak with your doctor about ways to help you stop.