According to "The American Chiropractor," chiropractic care is not a direct form of treatment for allergies. However, regular adjustments help boost your immune system. A better-functioning immune system decreases your chance of allergy-related illnesses such as sinus infections. Chiropractic care is also designed to allow your body to heal itself from diseases. Overall, chiropractic adjustments for allergies help reduce symptom flareups.
More information available at: The American Chiropractor.