The human sense of smell adds to the enjoyment of life, helps to cement memories and serves as an early warning device to alert the body to the potential danger of environmental toxins. Allergic reactions to scents can result from a specific irritant or from a combination of components not easily identified. Approximately 30 percent of the population report sensitivities to scented products, and as of 2010, more than 5,000 fragrances are included in fragrances and cosmetics alone, according to The American Academy of Dermatology.
Classic Allergic Reactions
Contact dermatitis is the most common allergic reaction to fragrances, according to a study conducted by the Department of Dermatology at the University of Athens, and reported in the "Annals of Allergies, Asthma & Immunology." The classic symptoms of contact dermatitis--which include hives, sneezing and itching--can usually be managed by distancing one's self from the offending scent. Because manufacturers are not required to provide content information, identification of the allergen is particularly challenging. A skin patch test administered by a dermatologist may help to identify the offending ingredient.
Breathing Problems
Fragrances that irritate the respiratory system can cause asthma or asthma-like responses, such as difficulty breathing, coughing and wheezing. An allergic reaction to a scent can be a response to a single-note fragrance, a combination of chemicals or even the masking agents used to cover up scents for so-called unscented products. Fragrances are included in cleaning agents, personal care and cosmetic items, room deodorants, petroleum products and even in prepared foods. Perfumes are frequent triggers for an asthma attack, says FamilyDoctor.org. Oral steroids and anticholinergic medicines are frequently prescribed to provide relief from respiratory reaction, while corticosteroids are administered to control future outbreaks.
Multiple Chemical Sensitivities
Repeated exposures to fragrances can cause multiple chemical sensitivities, a syndrome called idiopathic environmental intolerances, or IEI, according to the American Academy of Allergy and Immunology. Although a controversial condition, a growing number of people report moderate to extreme allergic reactions to exposure to a variety of substances with strong scents. When the body is exposed repeatedly to the same allergens, the immune system can become sensitized and release histamine, a compound that dilates blood vessels, tightens airways and causes hives and itching. A severe whole body response to an allergen is called anaphylaxis, a life-threatening condition that requires immediate medical attention, explains MedlinePlus. The treatment for anaphylaxis is epinephrine, or adrenaline, a naturally occurring hormone that opens the air passages in the lungs.
