Learn what psoriasis is, what causes it & how to identify the different types of psoriasis


Living with psoriasis can have both physical and psychological impacts. As a condition that can cause discomfort, soreness and itching of the skin, we know that psoriasis can be challenging to live with. 


So whether you’re suffering from symptoms, you’ve just been diagnosed or you’re trying to navigate your way through the condition, we’ve got everything you need to know about psoriasis. 


So, what is psoriasis?


Psoriasis is a skin condition, thought to be related to a problem with the immune system, which causes flaky patches of skin, that can also have a scaly appearance. 


When a person has psoriasis, their skin produces too many new skin cells, too quickly, meaning patches of the skin can become itchy and inflamed. Typically, cell replacement can take 21-28 days, whereas skin cells are replaced in three to seven days with psoriasis. 


Due to the accumulation of skin cells, this can form raised plaques on the skin which can be red and pink or purple and brown in colour, depending on your skin tone. These can also form a silver and grey appearance on top, making them look like scales.


Psoriasis can develop anywhere on the body and can also affect the nails and the joints, but usually it occurs on the elbows, knees, scalp and back, although different types can appear on different areas of the body – but note, psoriasis is not contagious.


Who can get psoriasis?


Psoriasis is thought to affect around two in 100 people in the UK.


It can affect both men and women and can start at any age. Often, most cases of psoriasis develop in adults between the ages of 20 and 30 and between 50 and 60 years old, too.


The causes of psoriasis 


It’s not fully understood what causes psoriasis, however, it’s thought that psoriasis starts in the immune system where certain immune cells (T cells) become overactive.


The T cells act as if they were fighting an infection or healing a wound which can cause them to produce inflammatory chemicals. This then leads to the rapid growth of skin cells, forming psoriatic plaques, but it’s not yet clear what initially triggers the immune system to act in this way.


For some people, psoriasis can run in families, whereas others can experience flare-ups triggered by changes in the environment such as stress or anxiety, injury or illness, and hormonal changes. Certain medications can also cause a psoriasis flare-up, so it’s important to discuss any medication you’re taking – whether it’s a prescription or not, with your GP.


What are the symptoms of psoriasis?


There are several types of psoriasis, so symptoms can vary. However, some people with psoriasis can experience:


• Dry skin lesions 

• Itching and soreness

• Inflammation and redness


If you think you may have psoriasis, it’s important to speak to your GP.  


Get to know the different types of psoriasis 


There are several different types of psoriasis, so it’s important to look out for the different symptoms. Most people have one type at a time, although it is possible to have two types at once. Generally, psoriasis can go through phases of causing problems for a few weeks or months before easing, getting better, or stopping for a period of time. 


Plaque psoriasis 


Plaque psoriasis is known to be the most common type of psoriasis and can occur either alone or in combination with another form. 


The plaques are formed by the build-up of skin cells, and while everyone’s experience of psoriasis is different, many can endure red, sore and very itchy plaques with white or silvery scales. Typically, these plaques appear on elbows, knees, scalp and the back, but they can also appear elsewhere on the body.


Scalp psoriasis 


Scalp psoriasis is a form of plaque psoriasis. It causes patches of skin to be covered in scales but can also be prone to a thick build-up of scaly skin which may cause dandruff-like flakes to develop and fall from the scalp. 


This can be visible around the hairline, forehead, neck and behind the ears, making the scalp feel itchy and tight for some. In severe cases of scalp psoriasis, the thickness of the scales can cause thinning and sometimes loss of the hair, but this is usually only temporary. 


Guttate psoriasis 


Guttate psoriasis is a widespread rash of small spots (around 1cm), also known as ‘tear drop’ or ‘rain drop’ psoriasis due to the shape of the sores. It can occur at any age but is most common among children and teenagers, often triggered after a streptococcal throat infection. 


Guttate psoriasis can develop across the chest, back, arms and legs but can clear up in several weeks or months, depending on how soon it’s treated. However, some people may continue to have flare-ups or find that it evolves into plaque psoriasis. 


Nail psoriasis 


Around half of all people with psoriasis experience the condition in the nails. It can affect the fingernails, toenails – or both, and can cause nails to become loose or separate from the nail bed. Tiny dents can also develop which can grow abnormally or appear discoloured. It’s also possible for a person to have nail psoriasis without having it anywhere else on the body. 


Pustular psoriasis 


Although it’s not as common, pustular psoriasis can refer to two types of psoriasis: palmoplantar pustulosis (PPP), which affects the palms and soles, and generalised pustular psoriasis, which occurs the across the body. 


Palmoplantar psoriasis 


Palmoplantar psoriasis (PPP) causes small pustules to form on the palms or soles in very red patches. These pustules are fluid-filled which gives them a yellow or cream colour, with the darkened skin around the pustules becoming thick, flaky and prone to cracking. This type of psoriasis can be painful and make walking or using the hands difficult.


Generalised pustular psoriasis (GPP) 


Generalised pustular psoriasis is a rare but serious type of psoriasis that occurs on the body other than the palms or soles, and often requires emergency treatment. Like PPP, small pustules filled with fluid quickly develop on any area of the body and can merge into one another, creating large areas of pus. This can cause skin to be sore, tender and itchy, and can feel hot to the touch. As a result, a person with GPP can feel unwell with feverish symptoms such as a headache, high temperature and feeling tired. 


Psoriasis in sensitive areas


As psoriasis can occur all over the body, it can affect sensitive areas such as the face, armpits, genitals and skin folds.


On the face, as with other types of psoriasis, typical plaques with scaliness can appear. However, in flexural areas, the armpits or groin area, this appearance is less common. Instead, it appears shiny, bright red or dark on darker skin tones. 


External factors can impact the psoriasis on flexural areas which includes tight clothing rubbing on the skin, certain deodorants or antiperspirants, sanitary towels or tampons, harsh toilet paper and sexual intercourse. This can cause irritation, pain, and become very uncomfortable, and may make some people feel embarrassed or avoid intimacy.


If you’re struggling with psoriasis in sensitive areas, it’s a good idea to speak with your GP or a dermatologist for support and advice.


How is psoriasis diagnosed?


If you think you may have psoriasis, it’s important to see your GP. Often, psoriasis can be diagnosed by taking a look at the appearance of your skin.


In some cases, you may be referred to a dermatologist if your doctor is uncertain about your diagnosis, or if your condition is severe.


Can psoriasis be treated?


Psoriasis is a complex condition that is unique to each individual. Experiences can differ from person to person, from the amount of skin affected to the ways in which a person chooses to cope with their psoriasis.


Although there isn’t a cure for psoriasis, there are a range of treatments and products available that may help manage the effects of psoriasis on a short term basis. However, treatments and products may only provide mild relief and it can be a case of trial and error to find what works for the severity and type of psoriasis that you have.


It’s important that both the physical signs and psychological impact of psoriasis are regularly assessed together, so the appropriate treatment can be prescribed. 


Boots Online Doctor Psoriasis service* may be able to advise on what is best for you, following a consultation with a clinician. To find out more about psoriasis and the available treatments, visit Boots Online Doctor, or speak to your GP for further advice.


*Access to treatment is subject to a consultation with a clinician to assess suitability and eligibility. Charges apply.

*Subject to availability and clinician approval. Charges apply.