Psoriasis vs. Eczema: What's Causing My Itch?

Psoriasis and eczema are two common skin conditions that cause significant discomfort due to red, itchy, and inflamed skin patches. Although both conditions are chronic and share symptoms like inflammation, they are distinctly different diseases. Determining whether you have psoriasis or eczema is crucial for managing the condition effectively, as each requires a different approach to treatment.

Prevalence and Age of Onset

Psoriasis generally appear later in life between 15 and 30 where as eczema often begins in infancy or early childhood

Psoriasis

Psoriasis is a relatively common skin condition affecting about 2-3% of the U.S. population. It typically manifests in early adulthood, with the most common onset age ranging between 15 and 35 years. This condition affects both men and women equally and can vary in severity.

Eczema

Eczema affects approximately 10-20% of infants and about 3% of adults and children in the U.S. Eczema is one of the most frequent skin conditions, among younger populations. Many individuals experience their first symptoms before the age of 5, although it can also first appear during adolescence or adulthood. While some children may outgrow eczema, others continue to experience symptoms into adulthood.

Causes

Psoriasis

Psoriasis is an autoimmune disease, characterized by the rapid overproduction of skin cells, resulting in thick, scaly patches. Genetics play a crucial role in the development of psoriasis, and it can be triggered or worsened by stress, infections, and physical injuries to the skin.

Eczema

Eczema, also known as atopic dermatitis, involves a complex interaction of genetics, environmental factors, and immune system. It is commonly found in individuals with a family history of eczema, allergies, or asthma. The exact cause of eczema is still not fully understood, and unlike psoriasis, it primarily affects the skin’s barrier function, leading to inflammation and irritation.

Psoriasis is clearly defined as an autoimmune condition whereas eczema is more often associated with immune system dysregulation and environmental factors. Both conditions reflect an underlying issue with immune system functioning but differ in their specific pathological processes and triggers.

Triggers

While both conditions can be triggered by stress and environmental factors, psoriasis is more closely linked to immune system responses and physical impacts on the skin, whereas eczema is more frequently connected to allergens and direct skin irritants.

Psoriasis

• Infections: Particularly streptococcal throat infections can trigger guttate psoriasis
• Stress: High stress levels can initiate or worsen psoriasis flare-ups
• Medications: Certain medications, including beta-blockers and lithium, can trigger psoriasis
• Injury to the skin: Cuts, scrapes, or sunburn can prompt the formation of psoriatic skin lesions
• Alcohol and Smoking: Both can increase psoriasis severity

Eczema

• Allergens: Pollen, dust mites, pet dander, mold
• Irritants: Soaps, detergents, shampoos, disinfectants
• Foods: Certain foods may trigger eczema in some people, especially those with food allergies
• Fabrics: Rough materials, such as wool or synthetic fibers, can irritate the skin
• Temperature and Humidity: Extremes in weather and low humidity levels can lead to skin dryness and trigger eczema

Signs and Symptoms

Both psoriasis and eczema can cause significant discomfort and may have similar symptoms like redness and itching. However, the nature of the lesions differs: dry and scaly for psoriasis versus moist and weepy for eczema.

Psoriasis

Psoriasis is characterized by the thick, red patches of skin covered with silvery scales. These patches, known as plaques, can appear on various parts of the body, including the scalp, elbows, knees, and lower back. These plaques are typically well-defined and dry, and they can be both itchy and painful. Unlike eczema, psoriasis is less likely to cause oozing or weeping lesions, and the scales are usually silvery-white.

Eczema

Eczema causes red, inflamed skin that can intensely itch and lead to the formation of small, fluid-filled blisters. These blisters may weep when scratched or broken. Eczema commonly affects the folds of the skin, such as behind the knees and inside the elbows, but can also appear on the face, neck, and hands. The skin may become scaly, and excessive scratching can lead to open sores and increased risk of infection.

Treatments

Psoriasis

Treatments aim to reduce inflammation, slow the rapid growth of skin cells, and remove scales. Effective management also seeks to minimize potential triggers to prevent or reduce the frequency of flare-ups.

• Topical Treatments: Corticosteroids, vitamin D analogues, and retinoids are applied directly to the skin to reduce inflammation and slow down cell turnover
• Phototherapy: Exposure to ultraviolet light, under medical supervision, can effectively slow skin cell growth and reduce scaling and inflammation
• Systemic Medications: For moderate to severe psoriasis, doctors may prescribe oral or injected medications that work throughout the body. These include methotrexate, cyclosporine, and biologics, which target specific parts of the immune system that drive inflammation
• Lifestyle Modifications: Patients are often advised to maintain a healthy lifestyle, which includes a balanced diet, regular exercise, and avoidance of known triggers such as stress and smoking

Eczema

Eczema treatments focus on hydrating the skin, reducing inflammation, and alleviating itching to prevent the cycle of skin irritation and damage through scratching. The main objective is to maintain skin barrier function, reduce exposure to irritants, and manage symptoms to enhance comfort and prevent infections.

• Moisturizers: Applying moisturizers daily is crucial to keep the skin hydrated and to repair the skin barrier
• Topical Steroids: These are used to reduce swelling, redness, and itchiness during flare-ups
• Antihistamines: These can help control itching, especially at night
• Topical Calcineurin Inhibitors: Patients are often advised to maintain a healthy lifestyle, which includes a balanced diet, regular exercise, and avoidance of known triggers such as stress and smoking
• Phototherapy: Like psoriasis, light therapy can be used to treat severe cases of eczema that do not respond to other treatments
• Immunosuppressants: In severe cases, medications that suppress the immune system might be considered to control symptoms

While both conditions utilize similar strategies such as topical treatments and phototherapy, psoriasis treatments often involve systemic medications that target specific immune responses due to its autoimmune nature. Eczema treatments, on the other hand, heavily emphasize skin care routines to protect and restore the skin barrier, alongside managing environmental and lifestyle factors that might trigger symptoms.