Formaldehyde is a strong sensitizer, meaning that exposure to formaldehyde can induce an allergic reaction. Skin rashes are the most common form of formaldehyde allergy, especially when the skin is exposed to liquid formaldehyde. Allergic skin reactions can also result from exposure to formaldehyde present in dry products, such as new permanent press clothing,when moistened with sweat. Airborne formaldehyde may cause allergic reactions in occupationally exposed persons, and also may result in a worsening of asthma symptoms in people with asthma. Allergens, other volatile chemicals, and a variety of medical conditions can cause some of the same symptoms as formaldehyde does. As with any
medical condition, persons with symptoms should have a thorough medical exam to identify the cause.