Psoriasis

Psoriasis is a long-term inflammatory condition that mainly affects the skin. Inflammation means that part of the immune system is more active than usual. This makes skin cells build up too quickly, creating thickened or scaly areas called plaques.

Plaques can appear anywhere, but they commonly affect the scalp, elbows, knees, lower back, hands, and feet. Psoriasis may also affect the nails. On lighter skin, plaques often look pink or red with silvery scale. On darker skin, they may look purple, dark brown, or grey, sometimes with less obvious redness.

Psoriasis is not contagious. You cannot catch it through touch, shared towels, swimming, sex, or close contact.

The condition tends to come and go. A period when symptoms worsen is called a flare. Treatment can reduce inflammation, clear or improve plaques, and make flares less frequent. Psoriasis cannot currently be cured, but many people achieve good long-term control.

Some people with psoriasis develop inflammation in their joints, called psoriatic arthritis. Recognising joint symptoms early matters because treatment can help prevent lasting joint damage.

The appearance and severity of psoriasis differ from person to person. Some people have a few small patches. Others have larger areas of affected skin.

Common symptoms include:

• Raised, inflamed patches covered with dry scale
• Itching, burning, soreness, or tight-feeling skin
• Cracked skin that may bleed
• Flaking from the scalp or other affected areas
• Pitted, thickened, discoloured, or lifting nails

Plaque psoriasis is the most common form. Other patterns include small drop-shaped spots, known as guttate psoriasis, and smooth patches in skin folds, known as inverse psoriasis. Pustular psoriasis causes pus-filled bumps that are not usually due to infection. Erythrodermic psoriasis causes widespread redness or discolouration and shedding of the skin.

Symptoms may affect sleep, clothing choices, work, exercise, relationships, and self-confidence. Psoriasis in the genital area, hands, feet, face, or scalp can have a major effect even when the total affected area is small.

Joint symptoms can include pain, swelling, stiffness, or warmth. Fingers or toes may swell along their whole length. Morning stiffness, heel pain, and back stiffness that improves with movement can also occur.

Psoriasis develops through a combination of immune activity, inherited risk, and environmental factors. It is not caused by poor hygiene, an allergy, or something you have done.

Psoriasis can run in families, but inheritance is not simple. Having a relative with psoriasis increases the possibility of developing it, but many people have no known family history. Not everyone with inherited risk develops symptoms.

Certain events or exposures may trigger the first episode or a later flare. Possible triggers include:

• Skin injury, including cuts, burns, tattoos, or sunburn
• Infections, especially a streptococcal throat infection
• Emotional stress
• Smoking or heavy alcohol use
• Cold, dry weather
• Some medicines

Medicines associated with psoriasis flares include lithium, some beta blockers like metoprolol or propranolol, antimalarial medicines, and certain immune treatments. Suddenly stopping systemic corticosteroids may also cause serious worsening. Do not stop a prescribed medicine on your own; ask the prescriber to review it.

Higher body weight is associated with more severe psoriasis and may make some treatments less effective. It is one factor among many and is not the sole cause of the condition.

Psoriasis is usually diagnosed by examining your skin, scalp, and nails and discussing how the symptoms developed. There is no single blood test that confirms ordinary skin psoriasis.

A clinician may ask about itching, pain, recent infections, family history, medicines, and previous skin treatments. They may also check for joint pain, swelling, or stiffness.

Psoriasis can sometimes resemble eczema, fungal infection, or other inflammatory skin conditions. If the appearance is unusual or the diagnosis remains uncertain, a small skin sample may be removed under local anaesthetic. This is called a skin biopsy. A laboratory then examines the sample under a microscope.

Joint symptoms may require a separate assessment. Blood tests and imaging can help rule out other causes or assess joint damage, but no single test confirms psoriatic arthritis in everyone.

Treatment is chosen according to the psoriasis pattern, where it appears, how much skin is affected, and how it affects your daily life. Previous treatment results, other health conditions, pregnancy plans, and personal preferences also matter.

Moisturisers, also called emollients, soften scale and reduce dryness or cracking. They can be used alongside other treatments but may not control inflammation by themselves.

Topical medicines are applied directly to the skin. They include corticosteroids like prednisone or hydrocortisone, which reduce inflammation, and vitamin D–related medicines, which slow excess skin-cell growth. Other options may be used for particular areas. The face, skin folds, and genitals usually need different treatment from thicker plaques because their skin is more sensitive.

Medicines applied to the scalp may come as solutions, foams, shampoos, gels, or oils. Treatment instructions matter because using too little may not help, while using some topical medicines for too long can cause side effects.

Phototherapy exposes the skin to controlled ultraviolet light in a medical setting. It is different from using a tanning bed. Treatment usually requires repeated visits over a set period. Phototherapy may be considered when topical treatment has not provided enough control or psoriasis covers a wider area.

Systemic treatments work throughout the body. They include tablets or injections that reduce specific parts of immune activity. Examples include traditional immune-modifying medicines, oral targeted treatments, and biologic medicines. Biologics are engineered proteins that block particular immune signals involved in psoriasis.

Systemic treatments may require blood tests, infection screening, or other monitoring. Some affect pregnancy or the immune response to infections and vaccines. Your treatment team should explain the expected benefits, monitoring, and important side effects before treatment begins.

Treatment can also include support for sleep, pain, mental health, or the practical effects of visible skin symptoms.

Medicines commonly used for this include acitretin, adalimumab, bimekizumab and methotrexate. Which one suits you, if any, is a decision for you and your doctor.

Psoriatic arthritis is an important possible complication. It can cause persistent joint pain, swelling, stiffness, and reduced movement. Early assessment and treatment may limit permanent damage.

People with psoriasis, especially more extensive psoriasis, have higher rates of some other health problems. These include cardiovascular conditions, high blood pressure, type 2 diabetes, inflammatory bowel conditions, anxiety, and depression. An association does not mean that everyone with psoriasis will develop them.

Nail psoriasis can be painful and may affect grip, walking, or fine hand movements. Cracked plaques can sometimes become infected, particularly if they are repeatedly scratched.

Widespread pustular or erythrodermic psoriasis can disrupt temperature control and fluid balance. These uncommon forms require urgent medical assessment.

There is no established way to prevent psoriasis because inherited and immune factors are involved. It is also not possible to guarantee that flares will stop completely.

Once psoriasis is present, recognising personal triggers may help reduce some flares. Protecting the skin from injury, avoiding smoking, limiting heavy alcohol use, managing stress where possible, and following the agreed treatment plan may help.

Do not avoid necessary medicines or vaccinations because you are worried about a possible flare. Ask for a medication review if symptoms began or worsened after starting a medicine.

Psoriasis usually follows a long-term pattern of flares and quieter periods. Plaques may clear fully with treatment, leave temporary colour changes, or return in the same places. Darker or lighter marks can remain after inflammation settles, especially on darker skin. These marks are not always active psoriasis and may fade slowly.

Treatment often needs adjustment over months or years. A medicine may work well for a long time and then become less effective, or your needs may change. Routine follow-up helps check skin and nail symptoms, treatment side effects, joint health, and the effect on daily life.

Psoriasis does not usually shorten day-to-day activities when it is well controlled. Most people can work, exercise, travel, have close relationships, and participate in sports. Swimming is safe, although chlorine may dry the skin. Psoriasis itself is not infectious.

Visible plaques can attract unwanted attention. Clear explanations to family, schools, or workplaces may help, but you are not required to discuss your condition with everyone. Psychological support can be useful if psoriasis is affecting your mood, confidence, or relationships.

Arrange a routine appointment if you have persistent scaly skin patches, unexplained nail changes, or symptoms that are not improving with your current plan. A review is also appropriate when treatment is difficult to use, causes side effects, or no longer controls your psoriasis.

Request a prompt assessment for new joint pain, swelling, morning stiffness, heel pain, or a whole swollen finger or toe. These symptoms do not always mean psoriatic arthritis, but they should not be ignored.

Seek urgent same-day medical help if psoriasis rapidly spreads, becomes intensely painful, or develops widespread pustules. Fever, chills, weakness, dehydration, or feeling seriously unwell alongside a major skin flare also need urgent assessment.

Call emergency services if you have widespread red or discoloured skin with severe illness, breathing difficulty, fainting, confusion, or signs of a severe allergic reaction. These are not features of an ordinary plaque psoriasis flare.

Is psoriasis contagious?

No. Psoriasis is caused by immune activity and cannot spread between people. Touching plaques, sharing a bed, swimming together, or having sex does not transmit it.

Can psoriasis go away permanently?

Symptoms can disappear for months or years, either naturally or with treatment. However, the underlying tendency remains, so psoriasis may return. There is currently no permanent cure.

Does stress cause psoriasis?

Stress does not fully explain why psoriasis develops, but it can trigger or worsen a flare in some people. Psoriasis itself can also create stress, leading to a difficult cycle. Stress support may help alongside medical treatment.

Is sunlight good for psoriasis?

Small amounts of sunlight may improve plaques for some people, but sunburn can worsen psoriasis and increases skin cancer risk. Medical phototherapy uses controlled ultraviolet exposure and is safer than trying to treat psoriasis with tanning beds or unplanned sun exposure.

What is the difference between psoriasis and eczema?

Both can cause inflamed, itchy skin. Psoriasis often produces more clearly defined, thick, scaly plaques, while eczema may be more intensely itchy and can ooze or crust. Their location and appearance can overlap, so an examination may be needed.

Can psoriasis affect my joints?

Yes. Psoriatic arthritis can occur before or after skin symptoms and sometimes affects people with limited psoriasis. Persistent pain, swelling, stiffness, heel pain, or swollen fingers and toes should be assessed promptly.