A simple allergy skin test takes about 30 minutes and will tell your doctor whether you have an allergy and exactly which allergens, such as seasonal tree or grass pollens, produce your symptoms. Antihistamines block the action of histamine, the chemical that is responsible for symptoms such as sneezing and runny nose. Nasal steroid sprays deliver a fine mist to the nose's lining and also suppress the allergic response. Prescription antihistamines and nasal sprays work best, without side effects, says Weiler. Nasal steroid sprays are often thought to be most effective treatment for the congestion and some of the runny nose, but they don't work quite as well for itching.
Antihistamines work best for itching.
The upside of OTC drugs is that they're cheaper, but the downside is that they have more side effects, are more likely to cause drowsiness and jitteriness. Those who have severe seasonal allergies for which nothing else works can get long-term relief with allergy shots. A recent study published in The New England Journal of Medicine showed that allergy shots have long-lasting effects, boosting the body's immune system for three years or more. The best advice, Weiler says, is to talk to your doctor. It sounds real simple to just pick up an OTC drug from the pharmacy, but that doesn't work for many people.