Psoriasis: symptoms, triggers, treatment and which doctor to see

What psoriasis is, how it looks on different skin tones, what triggers flares, the treatments a dermatologist uses, and why steroid creams need care.

What psoriasis is

Psoriasis is a long-term inflammatory condition of the skin. An overactive immune response speeds up the life cycle of skin cells, so new cells reach the surface in days rather than weeks. They pile up as thick patches covered in scale.

It is not an infection and it is not contagious: you cannot catch it by touching someone, sharing food or using the same towel. It is also not caused by poor hygiene. Psoriasis tends to come and go in flares, and although there is no cure, treatment can clear or greatly reduce the patches for long periods.

Psoriasis is more than skin deep. Some people develop psoriatic arthritis, and psoriasis is linked with a higher risk of heart disease, diabetes, fatty liver and depression. Good care looks at the whole person.

Symptoms

The most common type is plaque psoriasis. On darker Indian skin the patches often look purple, dark brown or grey rather than pink-red, and can leave dark marks when they heal. Typical features are:

• Raised scaly patches with clear edges, often on the elbows, knees, lower back and scalp
• Silvery-white scale that flakes off, and patches that may crack or bleed
• Itching, burning or soreness
• Scalp scaling that can extend beyond the hairline and is often mistaken for severe dandruff
• Nail changes — small pits, thickening, discolouration or the nail lifting off its bed
• Joint pain, stiffness or swelling, or a whole finger or toe becoming swollen, which may point to psoriatic arthritis

Other forms include small drop-like patches after a throat infection (guttate psoriasis), smooth red patches in skin folds, psoriasis on the palms and soles that is often confused with eczema or fungal infection, and rare severe forms with pus spots or redness over the whole body.

Causes, triggers and who is at risk

Psoriasis results from a combination of inherited tendency and immune activity. It often runs in families and can start at any age, most commonly in young adults. Things that can trigger or worsen flares include:

• Infections, especially a sore throat
• Stress
• Injury to the skin — cuts, scratches, tattoos or even rubbing — which can cause new patches at that spot
• Smoking and heavy alcohol use
• Excess body weight
• Some medicines, including certain blood pressure medicines and lithium, and stopping oral steroids suddenly
• Dry winter weather for some people

How it is diagnosed

A dermatologist can usually diagnose psoriasis with a careful skin examination, including your scalp, nails and skin folds, and by asking about your joints and family history. When the appearance is unusual, a small skin biopsy may be taken under local anaesthetic to confirm the diagnosis and rule out conditions that look similar, such as eczema, fungal infection or lichen planus.

Before some tablets or injections are started, blood tests are needed to check your blood count, liver and kidneys, and to screen for infections such as tuberculosis and hepatitis. If joint symptoms are present, X-rays or other tests may be arranged.

Which doctor to see

A dermatologist diagnoses and treats psoriasis and can manage it long term. See one if you have scaly patches that are not settling, scalp scaling that does not respond to anti-dandruff care, or nail changes. If you have joint pain, swelling or morning stiffness, a rheumatologist should assess you for psoriatic arthritis, because early treatment protects the joints.

You can find dermatologists in Bengaluru or rheumatologists in Bengaluru on The Doctor Index, each with a registration you can check.

Treatment

Treatment depends on how much skin is involved, where the patches are, whether joints are affected and how much the condition affects your life. Your dermatologist will often combine approaches.

Creams, ointments and moisturisers

Moisturisers used generously every day soften scale and reduce itching. Topical treatments for mild to moderate psoriasis include prescription steroid creams of different strengths, vitamin D-based creams, coal tar, salicylic acid to lift scale, and medicated shampoos for the scalp. Different strengths are used on different parts of the body, because skin on the face and folds is thin.

Phototherapy

Phototherapy uses controlled doses of ultraviolet light, usually narrowband UVB, given two or three times a week in a clinic over some weeks. It works well for widespread psoriasis. Ordinary sunbathing is not the same, and sunburn can worsen psoriasis.

Tablets and injections

For more extensive psoriasis, or when nails, scalp, palms or joints are badly affected, medicines that act on the whole body are used. These include methotrexate, cyclosporine and acitretin, as well as biologic medicines and newer targeted tablets that block specific parts of the immune response. All need regular monitoring. Some, such as acitretin and methotrexate, must not be taken during or shortly before pregnancy, so discuss family planning with your dermatologist.

Living with psoriasis

Psoriasis is easier to control when you know your triggers and keep up treatment between flares. Moisturise daily, avoid scratching or picking scale, stop smoking, keep alcohol low and aim for a healthy weight, which can also make treatments work better. Have your blood pressure, sugar and cholesterol checked regularly. Psoriasis can affect confidence and mood; if it does, tell your doctor, as support and better treatment both help.

When it is an emergency

Call 112 or 108, or go to the nearest emergency department, if you have:

• Redness and peeling spreading over most of the body, with chills, fever or feeling very unwell
• Sudden widespread pus-filled spots with fever
• A high fever or signs of serious infection while on methotrexate, biologics or other immune-suppressing medicines

These are uncommon, but severe forms of psoriasis can affect body temperature and fluid balance and need hospital care.

Questions to ask at your appointment

• What type of psoriasis do I have, and how severe is it?
• Which creams should I use on which areas, and for how long?
• Would phototherapy or tablets suit me better?
• Are any of my current medicines making it worse?
• Should I be checked for psoriatic arthritis?
• Which tests do I need while on this treatment?

Common questions

All dermatology conditions →

Sources

• MedlinePlus, US National Library of Medicine — Psoriasis
• World Health Organization — Global report on psoriasis
• MedlinePlus, National Library of Medicine — Psoriasis — Public-domain health-topic summary

Psoriasis: symptoms, triggers, treatment and which doctor to see is original text by The Doctor Index; the compiled source draft was used for research. Source: MedlinePlus, National Library of Medicine. Orphadata Science: Free access data from Orphanet. © INSERM 1999; July 2026 data, CC BY 4.0. This product uses the Human Phenotype Ontology (hp/releases/2026-09-01). Only sources listed for this article apply. Source material has been selected and arranged; HPO definitions are reproduced without alteration. No source organisation endorses this compilation. Köhler S et al. The Human Phenotype Ontology project: linking molecular biology and disease through phenotype data. Nucleic Acids Research 2014;42(D1):D966–D974. doi:10.1093/nar/gkt1026.

General information, not advice about your situation. Errors can be reported through the corrections process. Reference TDI-C-1980.