Location and Progression
Contact dermatitis can affect various parts of the body, depending on the area that comes into contact with the irritating substance or allergen. Among all body parts, the hands are the most commonly affected by contact dermatitis. For instance, hikers may develop contact dermatitis on their legs after brushing against poison ivy or a similar plant. Individuals with metal allergies may experience rashes on areas that frequently come into contact with metal, such as the neck, wrists, fingers, ears, and stomach. The onset of rashes can occur within minutes or take several hours after exposure. The duration of contact dermatitis varies depending on its severity, with some cases taking up to a month to completely disappear.
Diagnosis Methods for Contact Dermatitis
Diagnosing contact dermatitis can be accomplished through a straightforward clinical examination. During this process, the doctor will inquire about the timing of the rash’s onset as well as the patient’s occupation and hobbies. These questions often uncover potential exposure to irritants. In cases where allergic contact dermatitis is suspected, a patch test may be conducted. This test involves applying patches containing substances known to trigger common allergic reactions. By observing the patient’s reaction to these patches, doctors can identify the specific substance responsible for the dermatitis.