Psoriasis: Symptoms, Causes, Types, and Treatment Guide

What Is Psoriasis?

Psoriasis is a chronic, immune-mediated inflammatory skin disease that causes your body to produce new skin cells far too quickly. In healthy skin, cells grow and shed over a cycle of about 28 to 30 days.^[2] In psoriasis, that cycle compresses to just 3 to 4 days, and the result is visible: thick, raised patches covered in silvery-white scales that can feel rough as sandpaper under your fingertips.

Psoriasis is not simply dry skin. It is a systemic condition driven by an overactive immune system. Your T cells, which normally fight infections, mistakenly attack healthy skin cells. This triggers a cascade of inflammation that speeds up skin cell production and creates the visible plaques most people associate with the disease.^[3] Our complete eczema guide covers the full spectrum of immune-driven skin disease for comparison.

The condition can appear anywhere on your body. Elbows, knees, and the scalp are the most common sites, but psoriasis also affects the nails, palms, soles, and even the genital area. Severity ranges widely: a few small patches you can hide under a sleeve, or widespread coverage that makes getting dressed in the morning feel like a negotiation.

Understanding psoriasis starts with recognizing what it is not: not an infection, not caused by poor hygiene, and not something you can catch from another person. If you have ever wondered whether your rash might be something else entirely, our guide on types of skin rashes seen in adults can help you compare.

How Common Is Psoriasis?

Psoriasis is far more common than most people realize. Global prevalence sits at approximately 2 to 3%, though rates vary significantly by region and ethnicity.^[1]

The disease follows a bimodal pattern of onset, with the first peak between ages 20 and 30 and a second between 50 and 60. If you developed psoriasis before 30, you are more likely to carry specific genetic markers and have a family history of the condition. That early-onset group also tends to experience more severe, more persistent disease. For a broader look at how hereditary factors shape inflammatory skin disease, see our guide on whether atopic dermatitis is hereditary.

Psoriasis affects people of every ethnicity, though prevalence tends to be higher in Western countries and lower in East Asian populations. These geographic differences likely reflect a combination of genetic background and environmental factors.

Psoriasis Is Not Contagious

One of the most persistent myths about psoriasis is that you can spread it through touch. You cannot. Psoriasis is an immune-mediated condition, not an infection. You cannot give it to someone by shaking hands, sharing a towel, or swimming in the same pool.

This misunderstanding causes real harm. Picture extending your hand for a handshake and watching someone pull back. Many people with psoriasis report exactly that kind of social stigma, along with avoidance and shame tied directly to the false belief that their condition is infectious. Correcting this myth matters for both public awareness and the emotional well-being of those living with the disease.

Knowing what psoriasis is not tells only half the story. The real question, and the one that shapes every treatment decision, is what drives it in the first place.

What Causes Psoriasis?

Psoriasis does not have a single cause. It emerges from a complex interaction between your genes, your immune system, and the environment around you. Think of it as a loaded gun: genetics loads it, and environmental triggers pull the trigger.^[4]

Researchers have identified dozens of genetic risk factors and a growing list of environmental triggers. No single gene or trigger is enough on its own; psoriasis develops when multiple risk factors converge in the same person at the same time.^[4]

Genetics and Family History

Your genes play a major role in psoriasis risk. How do we know? Twin studies make the case clearly. Identical twins share a concordance rate of approximately 35 to 72% for psoriasis, compared to 12 to 23% in fraternal twins. That gap confirms a strong genetic component, yet the fact that identical twins do not always match demonstrates something equally important: genes alone are not enough.

The strongest genetic link is a marker called HLA-Cw6, found in an estimated 60 to 65% of people with psoriasis compared to about 15% of the general population.^[5] This marker sits within the major histocompatibility complex, a region of your DNA that helps your immune system distinguish self from non-self.^[6]

• Family history risk: If one parent has psoriasis, your risk is about 10 to 15%. If both parents have it, your risk jumps to roughly 50%.^[7]
• Genome-wide studies: Researchers have identified over 80 genetic loci associated with psoriasis susceptibility, many linked to immune regulation pathways.^[8]
• Early-onset connection: People who develop psoriasis before age 30 are more likely to carry HLA-Cw6 and have a positive family history.

If you are curious about how autoimmune mechanisms work across skin conditions, our article on whether atopic dermatitis is an autoimmune disorder explores the broader immune landscape.

Common Triggers

Even with a genetic predisposition, psoriasis often stays dormant for years, sometimes decades, until something activates it. You might go through college without a single patch, then wake up one stressful Monday morning and find plaques spreading across your elbows. What changed? Triggers vary from person to person, but several patterns emerge consistently in research.

• Psychological stress: Approximately 40 to 80% of psoriasis patients report stress as a trigger for flares.^[9] Stress hormones like cortisol can amplify the inflammatory pathways that drive psoriasis.
• Infections: Streptococcal throat infections are a well-documented trigger, particularly for guttate psoriasis. Up to 80% of guttate cases may be preceded by streptococcal pharyngitis.
• Skin injury (Koebner phenomenon): Psoriatic lesions can develop at sites of skin trauma, including cuts, burns, tattoos, and even sunburn. This occurs in approximately 25 to 50% of psoriasis patients.^[10]
• Medications: Beta-blockers, lithium, antimalarials, and rapid withdrawal of systemic corticosteroids can all trigger or worsen psoriasis.^[9]
• Smoking and alcohol: Both are associated with increased psoriasis risk and severity.^[11]

The connection between stress and skin conditions runs deeper than most people expect. Your nervous system and immune system communicate constantly, and chronic stress can keep inflammatory pathways active long after the original stressor has passed.

The Immune System and Skin Cell Turnover

At the cellular level, psoriasis is driven by a specific branch of your immune system. Dendritic cells in the skin become activated and release a signaling molecule called IL-23, which in turn activates a type of T cell known as Th17. These Th17 cells produce IL-17 and other inflammatory cytokines that set off a chain reaction.^[3]

Here is what that chain reaction looks like in practice: those cytokines tell your skin cells (keratinocytes) to multiply at an abnormal rate. Instead of the normal 28-day cycle, keratinocytes rush to the surface in just 3 to 4 days and pile up faster than your body can shed them. Run your finger across a psoriatic plaque and you can feel the result: layers of cells stacked like pages in a book, rough and silvery at the surface.

Emerging research also points to the skin microbiome as a factor. Dysbiosis, an imbalance in the microbial communities on your skin, may contribute to the inflammatory environment that sustains psoriasis.^[12] Studies have found differences in the bacterial composition of psoriatic plaques compared to unaffected skin.^[13]

The practical takeaway: psoriasis requires a genetic foundation, an immune system primed for overreaction, and an environmental trigger to set the process in motion. Remove any one of those three, and the disease may never appear.

Knowing what drives psoriasis helps, but recognizing it on your skin is the first step toward getting the right diagnosis.

Recognizing Psoriasis Symptoms

Psoriasis has a distinctive appearance, but it does not look the same on everyone. Your skin tone, the type of psoriasis you have, and where it shows up on your body all influence what you see in the mirror. Recognizing the signs early can help you seek treatment before the condition progresses.

What Psoriasis Looks Like

The classic psoriasis plaque is a well-defined, raised patch of skin covered with silvery-white scales. On lighter skin, the underlying patch appears red or salmon-colored.^[2] On darker skin tones, the same plaques may look violet, dark brown, or grayish, with scales that appear more silvery or grayish-white. The texture, though, is consistent across skin tones: dry, rough, and often flaking onto your clothes and bedsheets.

This difference matters. Psoriasis on darker skin is frequently underdiagnosed or misdiagnosed because the classic "red plaque" description does not match what clinicians see.^[14] If you have darker skin and notice thick, scaly patches that do not respond to standard moisturizers, psoriasis should be on the list of possibilities.

Common symptoms you may notice include:

• Itching: Affects approximately 70 to 90% of people with psoriasis, ranging from mild to severe
• Burning or soreness: Especially around active plaques^[15]
• Dry, cracked skin: May bleed, particularly on the hands and feet^[2]
• Thickened or ridged nails: Nail changes affect about 50% of psoriasis patients^[16]
• Auspitz sign: Pinpoint bleeding when scales are removed, a classic diagnostic clue

If you have scalp involvement, you may wonder about the best way to care for your hair. Our guide to scalp eczema treatment also covers overlapping scalp conditions that can be confused with scalp psoriasis. Our guide on whether to cut your hair if you have psoriasis addresses that specific concern.

Beyond the Skin: Nails and Joints

Psoriasis often extends beyond the skin surface. Nail psoriasis causes pitting (small dents in the nail plate), discoloration, thickening, and in severe cases, crumbling or separation of the nail from the nail bed.^[16] The result can be more than cosmetic: buttoning a shirt, peeling an orange, even typing on a keyboard becomes surprisingly difficult. If you are also experiencing hand involvement, our guide on why hand eczema won't heal covers overlapping management strategies for chronic hand and nail conditions.

Joint symptoms deserve special attention. About 30% of people with psoriasis develop psoriatic arthritis, a condition that causes joint pain, stiffness, and swelling.^[17]

The symptoms you experience depend partly on which type of psoriasis you have, and identifying your specific form helps your dermatologist choose the right treatment approach.

Types of Psoriasis: An Overview

Psoriasis is not a single disease but a family of related subtypes, each with its own appearance, typical location, and clinical behavior. Knowing which type you have helps guide treatment decisions and set realistic expectations for how the condition may progress.

Common and Rare Forms

Plaque psoriasis is by far the most common form, accounting for approximately 80 to 90% of all cases.^[19] If you have ever peeled a silvery flake off your elbow and watched it drift onto a dark sweater, this is likely the type you know. The other forms are less common but important to recognize:

• Guttate psoriasis: Small, drop-shaped lesions that often appear suddenly after a streptococcal infection. More common in children and young adults.^[20]
• Inverse psoriasis: Smooth, red patches in skin folds such as the armpits, groin, and under the breasts. Lacks the typical scale because of moisture in these areas.
• Pustular psoriasis: White, pus-filled blisters surrounded by red skin. Can be localized (palms and soles) or generalized, which is a medical emergency.^[21]
• Erythrodermic psoriasis: The rarest and most severe form, covering most of the body with a fiery red, peeling rash. Requires immediate medical attention.

For a deeper look at one of the more distinctive subtypes, see our detailed guide on guttate psoriasis.

Knowing your type is one piece of the puzzle. Treatment effectiveness varies dramatically by subtype and severity, so understanding the full range of options can help you and your dermatologist find the right fit faster.

Psoriasis Treatment: A Broad Landscape

Psoriasis treatment follows a stepwise approach: dermatologists typically start with the least invasive options and escalate based on severity, location, and how well you respond. The goal is not just to clear plaques but to reduce inflammation, slow cell turnover, and improve your overall quality of life.

Here is the encouraging part: about 80% of people with psoriasis have mild to moderate disease that can be managed with topical treatments alone.^[22] The remaining 20% may need phototherapy, systemic medications, or biologic therapies to achieve adequate control.^[23]

Topical Therapies

Topical treatments are the foundation of psoriasis care, working directly on the skin to reduce inflammation, slow cell growth, and soften scales.

• Corticosteroids: The most commonly prescribed topical treatment. Available in varying strengths for different body areas.
• Vitamin D analogues: Calcipotriol and calcitriol slow skin cell growth and are often combined with corticosteroids.^[24]
• Coal tar: One of the oldest psoriasis treatments, still effective for reducing scaling and itching.^[25]
• Emollients and moisturizers: Essential for maintaining the skin barrier and reducing dryness between flares.
• OTC keratolytics: Over-the-counter products containing sulfur or salicylic acid can help reduce scaling.
• SmartLotion: SmartLotion takes a different approach from standalone OTC products by combining anti-inflammatory, prebiotic, and moisturizing action in one formulation, addressing inflammation and the skin microbiome together rather than treating one symptom at a time.

Every treatment plan should be individualized. What clears one person's elbows in weeks may do nothing for another's scalp, and the best approach often combines multiple therapies.

Systemic and Biologic Options

When topical treatments are not enough, dermatologists turn to systemic therapies that work throughout the body. Traditional options include methotrexate, cyclosporine, and acitretin, each with its own benefit and risk profile.^[26]

Biologic therapies have transformed severe psoriasis management over the past two decades. These targeted medications block specific immune molecules involved in psoriasis, including TNF-alpha, IL-17, and IL-23.^[27] Clinical trials have shown that many patients achieve 75% or greater improvement in their psoriasis severity scores with biologic therapy.^[28]

For a broader look at how treatment approaches compare across inflammatory skin conditions, see our overview of atopic dermatitis treatments.

Because treatment choices hinge on an accurate diagnosis, understanding how dermatologists identify and classify psoriasis is worth your time.

How Psoriasis Is Diagnosed

Unlike many chronic diseases, psoriasis is primarily a clinical diagnosis. An experienced dermatologist can usually identify it based on the appearance and distribution of your skin lesions alone, without blood tests or special imaging.

Clinical Examination and Biopsy

During your appointment, your dermatologist will examine your skin, nails, and scalp, looking for the characteristic features of psoriasis: well-defined borders, silvery scale, and typical distribution patterns.

A skin biopsy may be needed when the diagnosis is uncertain. This is more common in atypical presentations, early disease, or when psoriasis overlaps with other conditions.^[29] Under the microscope, psoriatic skin shows distinctive features including thickened epidermis, elongated rete ridges, and collections of neutrophils in the upper skin layers.

Differential diagnosis is important because several conditions can mimic psoriasis. These include eczema, seborrheic dermatitis, fungal infections, and pityriasis rosea. If you are unsure whether your skin condition is psoriasis or eczema, our comparison guide on the difference between psoriasis and eczema can help clarify.

Measuring Severity

Once diagnosed, your dermatologist will assess how severe your psoriasis is. This classification directly influences which treatments are appropriate for you.

Note: Severity thresholds vary by guideline. Some classification systems use higher BSA cutoffs (e.g., mild <10%, moderate 10–20%, severe >20%). The thresholds above reflect the International Psoriasis Council approach, which accounts for impact on quality of life at lower BSA levels.

The Psoriasis Area and Severity Index (PASI) combines redness, thickness, scaling, and body surface area into a single score.^[31] Body Surface Area (BSA) provides a simpler estimate: your palm (including fingers) represents roughly 1% of your total body surface.

What this means for you: severity classification is not just academic. It determines which treatments your insurance will cover and which therapies your dermatologist can prescribe.

Severity also predicts something many people do not expect: your risk of developing other serious health conditions, from cardiovascular disease to depression.

Psoriasis Comorbidities: More Than Skin Deep

Psoriasis is not just a skin disease. The same inflammatory processes that drive plaques on your skin also circulate through your bloodstream, reaching your joints, blood vessels, and metabolic systems. Understanding these connections is essential for protecting your long-term health.

Psoriatic Arthritis

Psoriatic arthritis (PsA) develops in approximately 30% of people with psoriasis, making it one of the most significant comorbidities of the disease.^[17] It can affect any joint but commonly targets the fingers, toes, wrists, knees, and ankles. Understanding how immune reactions drive inflammatory skin and joint disease can help you recognize early warning signs.

What makes PsA tricky is timing. It can develop years before or after skin symptoms appear, and in about 15% of cases, joint symptoms actually precede the skin disease.^[32] That stiff knee you blamed on the gym? It could be the first sign. Early detection is critical because delays in diagnosis and treatment lead to irreversible joint damage.^[18]

Cardiovascular and Metabolic Risks

The systemic inflammation in psoriasis does not stop at the skin. It circulates, increasing cardiovascular risk across the severity spectrum. One large study found that patients with severe psoriasis had a 58% increased risk of major cardiovascular events, including heart attack and stroke, even after adjusting for traditional risk factors like smoking and high cholesterol.^[33]

Metabolic syndrome is also more common. This cluster of conditions, including obesity, high blood pressure, elevated blood sugar, and abnormal cholesterol levels, affects approximately 30 to 40% of psoriasis patients compared to about 20% of the general population.^[34] Understanding how systemic inflammation connects skin and metabolic health is explored further in our article on lipids and skin barrier function.

• Type 2 diabetes: Psoriasis patients have a higher prevalence of insulin resistance and diabetes^[35]
• Inflammatory bowel disease: Crohn's disease is approximately 3.8 times more common in psoriasis patients^[36]
• Uveitis: Inflammatory eye disease occurs more frequently in psoriasis and PsA patients^[36]

Mental Health and Quality of Life

The emotional toll of psoriasis is profound and often underestimated by clinicians. Depression risk rises 1.4 to 1.7 times above the general population rate.^[37] Research on the hidden burden of chronic skin conditions shows that quality-of-life impacts are consistently underestimated by clinicians across all inflammatory skin diseases. Anxiety rates are similarly elevated, and patients with severe disease face a nearly twofold increased risk of suicidality.^[37]

Imagine skipping a beach trip because you dread the stares. Or canceling a date because a flare appeared overnight on your hands. These are not minor inconveniences. They are patterns that erode confidence, shrink social circles, and deepen isolation over time.

Sleep disruption compounds the problem. Itching and discomfort frequently interrupt sleep, leading to fatigue that worsens both physical and mental health. If you struggle with sleep, our guide on sleeping with skin conditions offers practical strategies that apply to psoriasis as well.

For strategies on building confidence while managing a visible skin condition, see our article on feeling confident with a skin condition.

Understanding these risks is the first step. Because daily habits can either fuel or calm the inflammation behind psoriasis, what you do between doctor visits matters as much as the prescriptions you fill.

Living with Psoriasis: Daily Management

Treatment from your dermatologist is essential, but what you do between appointments matters just as much. The right daily habits, applied consistently, can reduce flare frequency, ease symptoms, and shift how you feel when you catch your reflection each morning.

Skincare and Moisturizing

Keeping your skin well-moisturized is one of the simplest and most effective things you can do. That tight, pulling sensation you feel after a shower? It means moisture is already escaping. Emollients help restore the skin barrier, reduce scaling, and decrease the itch that drives so much of the daily discomfort. For guidance on choosing the right products, Dr. Harlan's recommended moisturizers list includes options suitable for psoriasis-prone skin.

Lifestyle Modifications

Several lifestyle factors have a measurable impact on psoriasis severity, and the evidence is strongest for weight management, smoking cessation, and dietary changes. For a practical overview of how daily habits affect inflammatory skin conditions, see our guide on bad habits that make skin conditions worse.

• Weight management: Losing 5 to 10% of body weight has been shown to improve psoriasis severity in overweight patients. Excess fat tissue produces inflammatory cytokines that fuel the disease.
• Smoking cessation: Smoking roughly doubles your risk of developing psoriasis and worsens existing disease.^[11] Quitting reduces both psoriasis severity and cardiovascular risk.
• Alcohol moderation: Alcohol can trigger flares, interfere with treatment effectiveness, and increase liver toxicity risk from systemic medications.^[40]
• Diet: A Mediterranean-style diet rich in fruits, vegetables, fish, and olive oil shows anti-inflammatory benefits that may help reduce psoriasis activity.^[41]
• Exercise: Regular physical activity reduces systemic inflammation and supports weight management.^[42]
• Stress management: Mindfulness, meditation, and cognitive behavioral therapy have all shown benefits for psoriasis patients.^[43]

For more on how food choices affect inflammatory skin conditions, see our article on how diet affects skin conditions.

Daily management is not a substitute for medical treatment. Think of it as an amplifier: the better your daily habits, the harder your prescriptions can work.

Age, hormones, and skin tone all shape how psoriasis appears and responds to treatment, so recognizing those differences can prevent misdiagnosis and months of unnecessary delay.

Psoriasis in Special Populations

Psoriasis does not affect everyone the same way. Age, hormonal status, and skin tone all influence how the disease presents, progresses, and responds to treatment. Overlook those differences, and some patients fall through the diagnostic cracks.

Children and Adolescents

Pediatric psoriasis affects approximately 1% of children, with onset before age 16 in roughly one-third of all psoriasis cases.^[44] While plaque psoriasis remains the most common subtype in children, guttate psoriasis appears more frequently in this age group than in adults, often erupting within weeks of a strep throat infection.^[44]

Children with psoriasis face unique challenges, especially during adolescence, when a visible skin condition collides with the intense pressure to fit in.^[45] Picture a 13-year-old refusing to wear shorts on a sweltering day because classmates stared at the patches on her knees. Bullying, social withdrawal, and reduced self-esteem are common concerns that parents and clinicians should address proactively.

Treatment in children also requires careful consideration. Many systemic medications approved for adults have limited safety data in pediatric populations, making topical therapy and phototherapy the preferred first-line approaches.^[46]

Pregnancy and Hormonal Changes

Pregnancy influences psoriasis in unpredictable ways. Approximately 40 to 60% of women experience improvement during pregnancy, particularly in the third trimester, a reprieve that can feel almost miraculous after years of flares.^[47] But the relief is often temporary. A subset of women experience worsening during pregnancy, and postpartum flares are common as hormone levels shift rapidly after delivery.^[47]

Psoriasis Across Skin Tones

For people with darker skin tones, psoriasis presents diagnostic challenges that contribute to underdiagnosis and delayed treatment. The erythema (redness) that defines psoriasis on lighter skin may appear violaceous, dark brown, or hyperpigmented on darker skin. What does that mean in practice? The condition can go unrecognized for months or even years.^[14]

Even after plaques clear, the story is not over. Post-inflammatory hyperpigmentation and hypopigmentation are more common and more persistent in darker skin, leaving visible marks that can be just as distressing as the plaques themselves.^[49] Clinical severity scoring tools like PASI, which rely heavily on redness assessment, may underestimate disease severity in these patients.

These disparities highlight the need for dermatologists trained in recognizing psoriasis across the full spectrum of skin tones, and for clinical scoring tools that do not rely solely on redness to measure severity.

Across every age group and skin tone, one source of confusion keeps coming up: telling psoriasis apart from eczema. The two conditions share surface-level similarities but require different treatments, so getting this distinction right can save you months of using the wrong approach.

Psoriasis vs. Eczema: Key Differences

Psoriasis and eczema are both chronic inflammatory skin conditions, but they differ in important ways. Both itch. Both flare without warning. And both can leave you staring at your skin wondering what exactly is going on. If you are unsure which one you have, the comparison below can help you start the conversation with your dermatologist.

Whether you are dealing with psoriasis, eczema, or something you cannot yet name, knowing when to seek professional help can mean the difference between years of manageable symptoms and years of unnecessary suffering.

When to See a Dermatologist

Many people with psoriasis wait too long before seeing a specialist. Months pass, symptoms worsen, and the appointment keeps getting pushed to next week. That delay has consequences: research shows early intervention improves long-term outcomes, reduces the risk of comorbidities, and prevents the psychological damage that comes from years of uncontrolled disease.^[52]

You should see a dermatologist if:

• Your symptoms are spreading or not responding to over-the-counter treatments^[52]
• You notice joint pain or stiffness, which may signal psoriatic arthritis^[18]
• Your psoriasis affects your quality of life, including sleep, work, or social activities^[37]
• You are considering pregnancy and need to adjust your treatment plan^[48]
• You have not been screened for cardiovascular or metabolic comorbidities^[33]

While you work with your dermatologist on a treatment plan, SmartLotion can help manage mild-to-moderate symptoms by addressing inflammation, the skin microbiome, and moisture in a single formulation. For specific guidance, see the psoriasis treatment protocol.

Red Flags That Need Urgent Attention

Certain psoriasis presentations require immediate medical care. Do not wait for a routine appointment if you experience any of the following:

Additional help docs are available for specific psoriasis presentations: scalp psoriasis protocol, flexure psoriasis protocol, and guttate psoriasis protocol.

Frequently Asked Questions About Psoriasis

What is the main cause of psoriasis?

Psoriasis has no single cause. It results from a combination of genetic predisposition and environmental triggers that activate the immune system. The HLA-Cw6 gene is the strongest known genetic risk factor, present in about 60 to 65% of patients.^[5] Triggers like stress, infections, and skin injury can initiate or worsen flares in genetically susceptible people.^[9]

Can psoriasis go away?

Psoriasis is a chronic condition with no known cure. However, many people experience periods of remission where symptoms partially or completely clear.^[53] With appropriate treatment, most patients can achieve significant improvement. Some people with mild disease may go months or years between flares.^[54]

Is psoriasis contagious?

No. Psoriasis is an immune-mediated condition, not an infection. You cannot catch it from touching someone who has it, sharing personal items, or any other form of contact.

What is the best thing to do for psoriasis?

The most important step is to see a dermatologist for an accurate diagnosis and personalized treatment plan. Daily moisturizing, trigger avoidance, and consistent use of prescribed treatments form the foundation of effective management. Lifestyle changes like maintaining a healthy weight, quitting smoking, and managing stress also make a measurable difference.

Can diet affect psoriasis?

Yes. Research supports a Mediterranean-style diet rich in anti-inflammatory foods like fish, olive oil, fruits, and vegetables.^[41] Weight loss of 5 to 10% in overweight patients has been shown to improve psoriasis severity. Alcohol consumption can trigger flares and should be moderated.^[40]

What is the difference between psoriasis and eczema?

Psoriasis produces thick, well-defined plaques with silvery scale, typically on the elbows, knees, and scalp. Eczema causes red, inflamed, often weeping patches, usually in skin folds. They involve different immune pathways: psoriasis is Th17-driven, while eczema is Th2-driven.^[3][51] For a full comparison, see our guide on the difference between psoriasis and eczema.

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