Psoriasis Diagnosis and Treatment in London

Understanding psoriasis

Psoriasis is an immune-mediated condition that accelerates the life cycle of skin cells, causing a build-up of thickened, inflamed plaques. It can vary from small localised patches to widespread disease. Psoriasis can affect the scalp, nails, and skin folds, and some people develop joint symptoms known as psoriatic arthritis.

Psoriasis symptoms

• Raised, red plaques with silvery-white scales
• Itching, soreness, or burning sensations
• Dry, cracked skin that may bleed
• Nail pitting, thickening, discolouration, or detachment
• Joint stiffness, swelling, or pain (possible psoriatic arthritis)

Where psoriasis can appear

Psoriasis can affect different areas in different ways. Identifying the sites involved helps tailor treatment effectively.

• Scalp: Thick scaling, redness, and flaking that may mimic severe dandruff.
• Nails: Pitting, lifting (onycholysis), thickening, or crumbly changes.
• Face: Often more sensitive and may need carefully selected topical therapy.
• Flexures/skin folds (inverse psoriasis): Smooth, shiny redness in armpits, groin, or under breasts.
• Hands/feet: Can crack, bleed, and significantly affect daily function.

Types of psoriasis

• Plaque psoriasis: The most common type, with raised red plaques and scaling.
• Guttate psoriasis: Small, droplet-shaped lesions, often after throat infections.
• Pustular psoriasis: White pustules surrounded by red skin.
• Inverse psoriasis: Smooth red patches in skin folds.
• Erythrodermic psoriasis: Severe, widespread redness and scaling; this can be a medical emergency.

Causes and triggers of psoriasis

Psoriasis arises from a combination of genetic predisposition and immune system overactivity. Even when the underlying tendency is present, flares are often influenced by triggers such as:

• Infections (e.g., streptococcal throat infection)
• Stress and emotional strain
• Cold weather and dry air
• Skin injury (Koebner phenomenon)
• Certain medications (e.g., beta-blockers, lithium, antimalarials)
• Alcohol and smoking

Psoriasis diagnosis

A dermatologist usually diagnoses psoriasis by examining the skin, scalp, and nails. In unclear cases, a small skin biopsy may be taken. We also screen for symptoms of psoriatic arthritis, as a significant proportion of people with psoriasis develop joint involvement.

Psoriasis treatment options

Treatment depends on severity, the areas involved, previous response to therapy, and the impact on quality of life. We take a stepwise, evidence-based approach and can escalate treatment safely when needed. You can also read more about our psoriasis treatment pathway.

• Topical treatments: Corticosteroids, vitamin D analogues, coal tar, and salicylic acid preparations where appropriate.
• Phototherapy: Controlled UV treatment for more widespread or resistant disease. Targeted options may include Excimer UVB phototherapy for localised plaques.
• Systemic medications: Options such as methotrexate, ciclosporin, or acitretin may be considered for moderate to severe psoriasis.
• Biologics: Targeted injectable therapies for more severe or treatment-resistant psoriasis (e.g., anti-TNF or anti-IL pathways), prescribed based on suitability and clinical criteria.
• Lifestyle and trigger management: Stress reduction, sleep optimisation, weight management where relevant, smoking cessation, and limiting alcohol can reduce flare frequency.

Psoriasis and overall health

Psoriasis is associated with systemic inflammation, and in some people it can correlate with broader health risks and wellbeing. During consultation, we may discuss joint symptoms, mood and confidence, and general health factors that can influence inflammation and treatment choices.

When to seek urgent help

Seek urgent medical advice if you develop widespread redness and scaling with feeling unwell, fever, rapidly spreading pustules, or significant skin pain — these can indicate severe forms of psoriasis that require prompt assessment.

Living with psoriasis

Psoriasis can affect self-confidence, relationships, and day-to-day comfort. With the right plan, most people achieve meaningful control and long periods of stability. Regular follow-up helps optimise treatment and monitor long-term safety.

Your first visit — what to expect

1. History: Symptoms, previous treatments, triggers, and family history.
2. Examination: Assessment of skin, scalp, nails, and joints.
3. Tests: Blood tests or biopsy if diagnosis is uncertain or to guide safe treatment.
4. Treatment plan: Tailored therapy based on severity, lifestyle, and clinical needs.
5. Follow-up: Monitoring response, adjusting treatment, and ensuring safety.

Reviewed by: Dr Mohammad Ghazavi (MD, FRCP, MRCP), Consultant Dermatologist
Skinhorizon Clinic, 4 Clarendon Terrace, Maida Vale, London W9 1BZ
Meet the team · Dermatologist London
Last reviewed: 22 August 2025