Psoriasis Vulgaris

What Is Psoriasis Vulgaris?

• Psoriasis vulgaris is the common form of psoriasis, also called plaque psoriasis.
• Typical psoriatic plaques are well-defined, raised, red or pink areas covered by dry, silvery-white scale. In darker skin, they may look brown or darker than surrounding skin.
• Common sites include elbows, knees, scalp and lower back, but psoriasis can occur almost anywhere.
• Some patients have only a few plaques; others develop extensive disease.
• Psoriasis can affect the nails and joints. Joint symptoms are important because psoriasis can be associated with psoriatic arthritis.

And no — it is not contagious: You cannot get psoriasis by touching, hugging, sharing food, swimming with or sitting next to someone who has it.

How Common Is Psoriasis?

• Worldwide: Psoriasis affects roughly 2–3% of the global population, although prevalence varies considerably between countries and populations.
• Age: It can begin at any age, with many patients developing it in young adulthood or later life.
• India: Indian studies report variation in prevalence and clinical patterns across regions and healthcare settings; psoriasis remains a common condition in dermatology practice.
• Course: Psoriasis usually follows a relapsing-remitting course, with periods of improvement followed by flares.

Why Does Psoriasis Happen?

Intrinsic factors — things inside the person

• Genetic tendency: Psoriasis often runs in families. Genes increase susceptibility but do not guarantee that a person will develop disease.
• Immune-system tendency: The immune system becomes overactive in pathways involving dendritic cells, T cells and cytokines such as TNF, IL-17 and IL-23.
• Biological factors: Age at onset, immune status and other biological factors can influence the pattern and severity.
• Associated conditions: Psoriasis is linked with psoriatic arthritis, obesity, hypertension, diabetes, abnormal cholesterol, fatty liver disease, inflammatory bowel disease, anxiety and depression.

Extrinsic factors — things around the person

• Skin injury: Cuts, scratches, burns, tattoos and other trauma can trigger psoriasis at the injured site — the Koebner phenomenon.
• Infections: Certain infections, especially streptococcal throat infection, can trigger psoriasis in susceptible people.
• Stress: A common patient-reported trigger and an important contributor to the stress–sleep–flare cycle.
• Smoking: Associated with higher psoriasis risk and potentially greater disease burden.
• Alcohol: Associated with psoriasis risk and may worsen disease in some people.
• Obesity and inactivity: Associated with psoriasis severity and can complicate treatment.
• Medicines: Lithium, some beta-blockers, antimalarials and withdrawal of systemic corticosteroids can worsen psoriasis in susceptible patients.

What Happens Inside the Skin?

• Healthy skin renews itself in an orderly way. In psoriasis, immune signals disturb this balance.
• Immune cells release inflammatory signals activating keratinocytes, and activated keratinocytes recruit and activate more immune cells, this creates a self reinforcing loop.

Why modern medicines work so well: Many newer treatments block a specific psoriasis signal such as TNF, IL-17 or IL-23 instead of broadly suppressing the entire immune system.

What Does Psoriasis Look and Feel Like?

• Raised, sharply defined plaques with scale.
• Commonly affects elbows, knees, scalp and lower back.
• Itching is common, but not everyone with psoriasis itches.
• Cracking can occur, especially on hands and feet.
• Scalp psoriasis can extend beyond the hairline and resemble severe dandruff.
• Nail psoriasis can cause pits, separation from the nail bed, thickening or yellow-brown discoloration.
• Genital and flexural psoriasis can be smoother and less scaly.

How Is Psoriasis Diagnosed?

• Usually clinical: An experienced dermatologist can usually diagnose plaque psoriasis from history and examination.
• Dermoscopy: May support diagnosis in selected cases.
• Skin biopsy: Not routinely required; considered when the appearance is unusual or a clinical mimic needs exclusion.
• Severity assessment: BSA, PASI, PGA and DLQI help measure disease burden and treatment response.
• Location matters: A small plaque on the face, hands, feet or genitals can be more disabling than its body-surface percentage suggests.

Investigations: What Tests Are Actually Needed?

• Straightforward psoriasis usually does not require blood tests just to confirm the diagnosis.
• Before systemic/biologic therapy: Tests are selected according to the proposed medicine and the patient's medical history.
• Common baseline checks: CBC, liver enzymes, kidney function and other medicine-specific tests.
• Methotrexate: Blood count, liver and kidney monitoring; alcohol and liver-risk assessment.
• Cyclosporine: Blood pressure and kidney function test.
• Acitretin: Liver tests and lipid profile are important; strict pregnancy-prevention.
• Biologics/targeted therapies: Latent tuberculosis and hepatitis screening before immunomodulatory treatment.
• Metabolic screening: Blood pressure, weight/BMI, glucose or HbA1c and lipid profile.
• Joint screening: Prolonged morning stiffness, swollen digits, heel pain and inflammatory back pain;

A useful rule:  The goal of investigations is not to 'prove' psoriasis with a blood test. It is to choose treatment safely and identify important associated conditions.

How Is Severity Judged?

Treatment: There Is No One-Size-Fits-All Plan

• Treatment depends on severity, location, symptoms, quality-of-life impact, previous therapy, other systemic illnesses, pregnancy plans, preference and access/cost.
• Modern care aims for clear or almost-clear skin and meaningful improvement in quality of life.

1. Topical Treatments

• Topical corticosteroids: Reduce inflammation, redness and scale.
• Vitamin D analogues: Calcipotriol/calcipotriene reduce abnormal epidermal growth and inflammation.
• Steroid + vitamin D combinations: Often effective because they combine complementary actions.
• Topical calcineurin inhibitors: Tacrolimus or pimecrolimus may be on face, folds and genital skin where steroid overuse is a concern.
• Keratolytics: Salicylic acid can soften thick scale and improve penetration of other treatments.
• Moisturizers: Reduce dryness, cracking and itch and improve comfort.

2. Phototherapy

• Narrowband UVB: Established treatment for widespread psoriasis, delivered repeatedly under medical supervision.
• 308-nm excimer laser: Targets psoriatic plaques while sparing much of the surrounding skin; useful for localized or resistant disease.
• PUVA: Effective in selected cases but used more selectively because of long-term safety considerations.
• Important: Phototherapy is controlled medical UV treatment — it is not the same as deliberate sunburn or tanning.

3. Conventional Systemic Medicines

• Methotrexate: Useful for moderate-to-severe psoriasis and psoriatic arthritis: laboratory monitoring is essential.
• Cyclosporine: Fast-acting option for selected severe/unstable psoriasis.
• Acitretin: Useful in selected patients, including some hyperkeratotic or pustular disease-palmer planter involvement ; strict reproductive precautions.
• Apremilast: Oral PDE-4 inhibitor for selected patients; gastrointestinal symptoms and weight changes can occur.

4. Biologic Treatments

• TNF inhibitors: Examples include adalimumab, etanercept, infliximab and certolizumab.
• IL-12/23 pathway:
• IL-17 pathway: Secukinumab, ixekizumab and brodalumab and bimekizumab.
• IL-23 pathway: Guselkumab, risankizumab, tildrakizumab and mirikizumab.
• Why they changed psoriasis care: Many patients achieve very high levels of skin clearance with targeted therapy. Choice depends on comorbidities, safety, cost, convenience and preference.

5. Targeted Oral Small Molecules

• Deucravacitinib: A selective TYK2 inhibitor.
• Why oral targeted therapy matters: Some patients prefer tablets over injections, while others prioritize maximum clearance, dosing frequency or a treatment suited to their joint or bowel disease.

Procedural & Device-Based Treatment

• 308-nm excimer laser: Useful for localized plaques, difficult sites or selected resistant lesions.
• NB-UVB: A medical phototherapy procedure for larger areas of psoriasis.

Diet: Can Food Make Psoriasis Better or Worse?

• Food is not the sole cause of psoriasis, and there is no single diet that cures it.
• Weight loss when overweight: Calorie-controlled weight reduction may improve psoriasis.
• Mediterranean-style eating: Vegetables, fruit, legumes, whole grains, nuts, fish and unsaturated fats support overall health.
• Omega-3 foods: Fish and omega-3-rich foods provide nutritional benefits.
• Gluten-free diet: Not routinely needed. Consider only when coeliac disease or relevant gluten sensitivity is present.
• Vitamin D: Supplement deficiency when indicated; taking high doses without a reason is not advisable.
• Ultra-processed foods: Reducing them can help weight and metabolic health.
• Practical message: Improve the overall quality of the diet rather than following long internet lists of forbidden foods.

Be careful with internet food lists:  There is no strong evidence that every person with psoriasis must avoid tomatoes, dairy, sugar, gluten or 'nightshades'. Individual triggers can exist, but universal bans are not evidence-based.

Smoking and Psoriasis

• Smoking is associated with a higher risk of developing psoriasis.
• It may also be associated with more severe disease and poorer overall health.
• Tobacco-related inflammatory and oxidative pathways may contribute to immune activation.
• Smoking also increases cardiovascular risk, which matters because psoriasis patients may have higher cardio-metabolic risk.
• Smoking cessation is therefore part of good psoriasis care, not merely general health advice.

Alcohol and Psoriasis

• Alcohol and psoriasis can reinforce each other: psoriasis can affect mood, while alcohol may be used to cope with stress.
• A positive association exists between alcohol consumption and psoriasis.
• Heavy alcohol use can complicate treatment through liver risk and poor adherence.
• Reducing or avoiding alcohol is especially important with medicines that carry liver-related concerns.
• Individual responses differ; the goal is to avoid harmful or heavy use and recognise personal flare patterns.

Stress, Sleep and Lifestyle

• Stress is a common reported trigger.
• Poor sleep can worsen itch, stress and quality of life.
• Regular physical activity is encouraged, especially because obesity, diabetes and cardiovascular risk commonly accompany psoriasis.
• A realistic routine beats a perfect routine that lasts three days.
• Walking regularly, improving sleep, stopping smoking, reducing alcohol and choosing healthier meals can support medical treatment.

Psoriasis and Psoriatic Arthritis

• Psoriatic arthritis can cause permanent joint damage if diagnosis and treatment are delayed.
• We ask about joint pain, swelling, morning stiffness, heel pain, sausage-like swelling of fingers/toes and inflammatory back pain.
• Joint symptoms can appear before, after or alongside skin disease.
• Early rheumatology assessment is important when symptoms suggest psoriatic arthritis.
• Treatment choice can change when significant joint disease or inflammatory bowel disease is present.

Psoriasis and the Rest of the Body

• Important associated conditions: psoriatic arthritis, obesity, hypertension, diabetes, dyslipidaemia, metabolic syndrome, fatty liver disease, inflammatory bowel disease, anxiety and depression.
• Why screening matters: These conditions affect overall health and can influence thepsoriasis treatment.
• Mental health: Visible psoriasis can affect confidence, relationships, work and social life. Anxiety and depression deserve active attention.

Latest Advances in Psoriasis Treatment

• IL-17 and IL-23 inhibitors: These have transformed moderate-to-severe plaque psoriasis, allowing many patients to achieve very high levels of clearance.
• TYK2 inhibition: Deucravacitinib is an important oral targeted approach not available in India.
• Treat-to-target: Modern care uses measurable clearance and quality-of-life goals rather than accepting inadequate control indefinitely.
• Personalized selection: Dermatologists increasingly match treatment to joint disease, bowel disease, obesity, cardiovascular risk, infection risk, pregnancy plans and patient preference.
• Combination strategies: Targeted phototherapy can be useful for selected stubborn/localized lesions, including partial responses during systemic therapy.

Prognosis: What Can a Patient Expect?

• Psoriasis is a chronic diseaseand not a one-time infection that can simply be eliminated.
• Some patients have long periods of minimal disease; others experience frequent flares.
• Modern therapies can produce near-complete or complete clearance in many patients, but stopping treatment can allow psoriasis to return.
• Recurrence does not mean treatment was useless; it reflects the chronic nature of psoriasis.
• Early treatment is worthwhile when disease affects sleep, mood, work, relationships or joints.
• With appropriate treatment and follow-up, many people with psoriasis lead normal, active lives.

How We Manage Psoriasis at DermaStation: A Practical Approach

• Confirm the diagnosis.
• Map the disease — skin, scalp, nails, sensitive areas and joints.
• Measure severity using BSA/PASI/PGA and ask about quality of life.
• Identify triggers and lifestyle factors such as smoking, alcohol, stress, obesity, skin trauma and relevant medicines.
• Screen for important comorbidities and psoriatic arthritis.
• Choose treatment matched to disease severity and the patient's priorities.
• Set a clear treatment target and review whether it has been reached.
• If response is inadequate, check adherence and diagnosis, then adjust, combine or switch treatment as appropriate.
• Continue long-term prevention and follow-up.

When Should You See a Dermatologist?

• Persistent red, scaly patches that keep returning.
• Scalp scaling that does not improve with ordinary anti-dandruff treatment.
• Thick plaques on elbows, knees, back or other sites.
• Nail changes with skin lesions or unexplained persistent nail dystrophy.
• Skin disease associated with joint pain or prolonged morning stiffness.
• Psoriasis affecting the face, genitals, hands, feet or scalp.
• Rapidly spreading, painful, cracking or sleep-disrupting disease.
• Frequent flares despite treatment.
• Side effects from prolonged steroid or self-treatment.

What Patients Should Avoid

• Do not stop prescribed systemic or biologic treatment without discussing it with your dermatologist.
• Do not use potent steroid creams on the face, groin or folds without medical guidance.
• Do not aggressively scrub or scrape plaques; trauma can trigger more psoriasis.
• Do not rely on detoxes, miracle creams or restrictive diets instead of proven treatment.
• Do not use tanning beds as a substitute for supervised phototherapy.
• Do not ignore joint symptoms.

Frequently Asked Questions