Though exercise does not appear to cause allergies, active patients re
quire special attention when allergies appear. Physical activity may i
ncrease contact with substances that cause hay fever, trigger asthma e
pisodes, or result in contact dermatitis. Nonspecific irritants (like
chlorine or air pollutants) and allergens often interact in the contex
t of exercise, and strenuous activity may produce allergic-like sympto
ms that complicate the clinical picture. An athletic patient's exercis
e patterns and preferences should be kept in mind in evaluating allerg
ies, devising treatment strategies, and choosing medication.