What Causes Allergic Dermatitis?

Allergic dermatitis is an allergic reaction triggered by allergens that affect the human immune system. Potential allergens include foods, medications, pollen, dust mites, dust, cosmetics, and more. If exposure to the allergen cannot be avoided, the condition often recurs; therefore, in addition to active treatment after onset, vigilant daily precautions are essential. But what exactly causes allergic dermatitis?

What Causes Allergic Dermatitis?

Allergic dermatitis encompasses a broad category of skin disorders. Any skin inflammation associated with an allergic response falls under this classification. Even when the specific allergen is difficult to identify, clinicians may still diagnose the condition as allergic dermatitis if allergy is suspected. While allergic dermatitis always involves an allergen, contact allergens—those encountered through direct skin contact—are among the most common in daily life. For instance, consuming spoiled or undercooked seafood may trigger a protein-based (peptone) allergic reaction, which also qualifies as allergic dermatitis. Many commonly used medications carry the risk of cutaneous allergic reactions; thus, when dermatitis develops, it is important to consider whether newly introduced medications could be the culprit.

Dust, cotton fibers, willow catkins, pollen, and other airborne particles easily inhaled via the respiratory tract constitute potential allergens. Seafood (e.g., fish, shrimp, crab), red meat (e.g., beef, lamb), eggs, milk, peanuts, soybeans, and other foods entering the body through the digestive system are also common allergenic sources. Clothing, cosmetics, jewelry, hair dyes, disinfectants, and other substances frequently contacting the skin represent additional potential allergens. Once the causative allergen is identified, strict avoidance is mandatory. If the specific allergen remains unknown, individuals should minimize exposure to all the aforementioned potential triggers in daily life. Preventing allergic dermatitis requires cultivating a clean, healthy, and hygienic living environment.

For patients with allergic dermatitis, the most critical dietary restriction is eliminating known allergens. For example, some individuals are allergic to milk and must therefore avoid dairy products entirely; others react adversely to fish, shrimp, or crab and must strictly exclude these from their diet. We hope this information proves helpful to you.