What Causes Eczema? Unraveling the Complex Web of Triggers and Factors

Understanding Eczema: An Overview

Eczema, pronounced eg-zuh-MUH, isn’t a single disease, but rather an umbrella term for a group of chronic inflammatory skin conditions. These conditions are characterized by dry, itchy skin, often accompanied by rashes, scaly patches, blisters, and even skin infections. While there are seven recognized types of eczema, they all share the distressing symptom of skin irritation and discomfort. It’s important to understand that eczema is not contagious, you cannot “catch it” from someone else. While there is currently no known cure for eczema, effective treatments and management strategies are available to help individuals live comfortably and minimize flare-ups.

Many individuals living with eczema describe periods of symptom exacerbation as “flares.” These flares can range from days to weeks, marked by intensified itching and other eczema symptoms. Severe eczema can lead to complications beyond the typical itch and rash, including infections that may necessitate hospitalization if left unaddressed. Because eczema can sometimes be mistaken for other skin conditions such as psoriasis, seeking a professional diagnosis from a healthcare provider is crucial for accurate identification and appropriate management.

The Intricate Web of Causes: What’s Behind Eczema?

The question “What Causes Eczema?” is complex, as there isn’t one single, definitive answer. Eczema development is generally understood to be a result of a combination of genetic predisposition and environmental factors. Researchers are continuously working to unravel the precise mechanisms, but we know that eczema arises from an interplay between your genes and the world around you.

Genetic Predisposition: Family History Matters

Genetics play a significant role in eczema susceptibility. If you have a family history of eczema, allergies like hay fever, or asthma, you have a higher chance of developing eczema. These conditions, often referred to as the “atopic triad,” are linked by similar underlying immune system dysregulation and a genetic component that can be passed down through families. While inheriting these genes doesn’t guarantee you’ll get eczema, it increases your likelihood of developing the condition when exposed to certain triggers.

The Skin Barrier Dysfunction: A Key Factor

A crucial factor in eczema development is a compromised skin barrier. Your skin’s outermost layer, the stratum corneum, acts as a protective shield, preventing moisture loss and blocking irritants and allergens from entering. In individuals with eczema, this skin barrier is often weakened or dysfunctional. This impairment can be due to genetic variations that affect the production of proteins like filaggrin, which are essential for maintaining a healthy skin barrier. When the skin barrier is compromised, it becomes more permeable, allowing irritants, allergens, and bacteria to penetrate more easily, triggering inflammation and eczema symptoms. This also leads to increased water loss from the skin, contributing to dryness, a hallmark of eczema.

Immune System Overactivity: Inflammation Unleashed

The immune system plays a central role in the development of eczema symptoms. While eczema is not classified as an autoimmune disease, it involves an overactive immune response. When the skin barrier is breached, or when the body encounters triggers, the immune system in people with eczema tends to overreact. This overreaction leads to inflammation in the skin, the root cause of the characteristic itch, redness, and rash. This inflammatory response is mediated by various immune cells and chemical messengers (cytokines), which are excessively produced in eczema-affected skin. Understanding this immune system component is key to developing targeted treatments that can help modulate this inflammatory response and alleviate eczema symptoms.

Environmental Triggers: External Irritants and Allergens

Environmental triggers are external substances or conditions that can provoke or worsen eczema flares. These triggers vary significantly from person to person, making eczema management a personalized process. Identifying and minimizing exposure to your specific triggers is a cornerstone of eczema management.

Common Environmental Triggers:

• Irritants: These substances directly damage the skin barrier, leading to inflammation. Common irritants include:

  • Soaps and detergents: Harsh soaps, laundry detergents, and dish soaps can strip the skin of its natural oils, drying it out and disrupting the skin barrier.
  • Fragrances: Perfumes, scented lotions, air fresheners, and fragranced cleaning products contain chemicals that can irritate sensitive eczema-prone skin.
  • Certain fabrics: Wool and synthetic fabrics can be rough and less breathable, causing friction and irritation.
  • Chemicals: Exposure to certain chemicals, such as those found in some cleaning solutions or industrial settings, can trigger eczema flares.
  • Cigarette smoke: Smoke is a potent irritant that can exacerbate eczema symptoms.

• Allergens: These substances trigger an allergic reaction in the immune system, leading to inflammation. Common allergens include:

  • Pollen: Seasonal pollen from trees, grasses, and weeds can trigger eczema, particularly in individuals with hay fever.
  • Dust mites: Microscopic creatures found in house dust are a common year-round allergen.
  • Pet dander: Proteins found in animal skin, saliva, and urine can trigger allergic reactions in sensitive individuals.
  • Mold: Mold spores, both indoor and outdoor, can be potent allergens.
  • Certain metals: Nickel, cobalt, chromium, and gold, commonly found in jewelry and some everyday objects, can cause allergic contact dermatitis, a type of eczema.
  • Latex: Natural rubber latex can trigger allergic reactions in some individuals.

• Climate and Weather: Environmental conditions play a significant role:

  • Dry air: Low humidity, especially in winter, can dry out the skin, weakening the barrier and triggering flares.
  • Extreme temperatures: Both extreme heat and cold can aggravate eczema. Heat can lead to sweating and irritation, while cold, dry air can worsen dryness.
  • Changes in temperature and humidity: Rapid fluctuations in weather can stress the skin and trigger flares.

Stress and Eczema: The Mind-Skin Connection

Stress is a well-recognized trigger for eczema flares. When you experience stress, your body releases cortisol, a stress hormone. Cortisol can directly impact the skin by disrupting the skin barrier function, exacerbating inflammation, and increasing the risk of skin infections. Managing stress through relaxation techniques, mindfulness, and lifestyle adjustments can be an important aspect of eczema management for some individuals.

Food Sensitivities and Eczema: A Possible Link

The relationship between food and eczema is complex and varies from person to person. While true food allergies (IgE-mediated) are less commonly a direct cause of eczema flares, food sensitivities or intolerances may play a role in some individuals, particularly children with atopic dermatitis. Certain foods might trigger a delayed immune response that can contribute to eczema symptoms. Common food culprits sometimes include dairy, eggs, soy, wheat (gluten), and nuts. However, it’s crucial to note that dietary changes should only be made under the guidance of a healthcare professional or registered dietitian. Elimination diets without proper medical supervision can lead to nutritional deficiencies, especially in children. Keeping a food diary and carefully monitoring symptoms can help identify potential food triggers, if any.

Diagnosing the Cause: Seeking Professional Help

While understanding potential causes and triggers is helpful, self-diagnosis of eczema type and its specific triggers is not recommended. Due to overlapping symptoms and varied triggers across different types of eczema, consulting a healthcare provider specializing in dermatology or allergy is crucial for accurate diagnosis and personalized management. A healthcare provider will take a detailed medical history, assess your symptoms, and visually examine your skin. They may also perform patch testing to identify specific allergens triggering contact dermatitis or recommend blood tests in certain cases. Based on the diagnosis, a customized treatment plan can be developed, and strategies to prevent future flares can be discussed.

Managing Eczema by Understanding the Causes and Triggers

Effective eczema management goes beyond just treating symptoms; it involves understanding and addressing the underlying causes and triggers. Once you and your healthcare provider have identified your specific triggers, the focus shifts to minimizing exposure and implementing preventative measures. This may involve:

• Avoiding identified irritants and allergens: Making conscious choices about skincare products, household cleaners, fabrics, and environmental exposures to minimize contact with known triggers.
• Maintaining a consistent skincare routine: Regularly moisturizing with emollients, especially after bathing, to maintain skin hydration and barrier function. Using gentle, fragrance-free cleansers.
• Managing stress: Incorporating stress-reducing techniques into your daily life, such as exercise, yoga, meditation, or spending time in nature.
• Addressing food sensitivities (if identified): Working with a healthcare professional to manage dietary factors, if food sensitivities are suspected to be contributing to your eczema.
• Environmental control: Using air purifiers to reduce airborne allergens, controlling dust mites in the home, and maintaining optimal humidity levels.

Treatment Approaches Based on Causes and Symptoms

Eczema treatment strategies are tailored to the individual and the severity of their condition. Treatments aim to reduce inflammation, relieve itching, repair the skin barrier, and prevent infections. Depending on the identified causes and triggers, treatment plans may include:

• Topical corticosteroids: Prescription creams and ointments that reduce inflammation.
• Topical calcineurin inhibitors (TCIs): Non-steroidal prescription medications that also suppress inflammation.
• Barrier repair moisturizers: Prescription or over-the-counter emollients specifically formulated to restore the skin barrier.
• Antihistamines: To help alleviate itching, especially at night.
• Biologics: Injectable medications that target specific parts of the immune system, used for severe eczema.
• Phototherapy: Ultraviolet light therapy, administered under medical supervision.
• Infection management: Antibiotics or antiviral medications if bacterial or viral infections develop.

Prevention: Minimizing Exposure to Triggers

Preventing eczema flares is an ongoing effort. By understanding what causes your eczema to flare, you can take proactive steps to minimize exposure to those triggers. This proactive approach, combined with consistent skincare and appropriate medical treatment, can significantly improve your quality of life and reduce the frequency and severity of eczema flares. Remember, managing eczema is a journey, and finding the right combination of strategies that work for you often requires patience and collaboration with your healthcare provider.

References:

1. Hanifin JM, Reed ML; Eczema Prevalence and Impact Working Group. A population-based survey of eczema prevalence in the United States. Dermatitis. 2007;18(2):82-91. doi:10.2310/6620.2007.06034
2. Lönndahl L, Abdelhadi S, Holst M, Lonne-Rahm SB, Nordlind K, Johansson B. Psychological Stress and Atopic Dermatitis: A Focus Group Study. Ann Dermatol. 2023;35(5):342-347. doi:10.5021/ad.22.035

Medically reviewed: January 27, 2025