Allergic rhinitis, often referred to as hay fever, is an inflammatory disease that causes sneezing, itchy or watery eyes, itchy or runny nose and congestion. For millions of sufferers, antihistamines and nasal corticosteroid medications provide temporary relief of these symptoms. For others, allergy shots—or subcutaneous immunotherapy—are a treatment option that can provide long-term relief, according to the American Academy of Allergy, Asthma & Immunology (AAAAI).

“Allergy shots involve two phases. The first phase involves frequent injections of increasing amounts of allergen extract. This is followed by a maintenance phase, during which the injections are given about once a month,” said Linda Cox, M.D., FAAAAI, a past president of the AAAAI.

Following the timetable

Although allergy shots are effective at controlling allergic rhinitis symptoms, the schedule can be difficult to maintain. Local reactions, for example swelling and itchiness at the injection site, are also common side effects. In addition, severe allergic reactions can occur but are relatively uncommon.

"If someone is allergic to ragweed and trees, ragweed tablets or shots would only help control ragweed symptoms during ragweed season. And while allergy shots can be tailored to include the variety of allergens a person is allergic to, the allergy tablets cannot.”

Another form of allergy immunotherapy was recently approved in the United States called allergy tablets, or sublingual immunotherapy. Allergy tablets involve administering the allergens in a tablet form under the tongue generally on a daily basis.

To date, the U.S. Food and Drug Administration (FDA) has approved three allergy tablet products. Two are directed at different kinds of grass pollen and one is for short ragweed. The main side effects of allergy tablets are local reactions such as itching or burning of the mouth or lips and, less commonly, gastrointestinal symptoms. These reactions usually stop after a few days or a week.

Comparing shots and tablets

The concept behind immunotherapy, regardless of its form, is that the immune system can be desensitized to specific allergens that trigger allergy symptoms. However, there are some differences between allergy shots and tablets when it comes to effectiveness and safety.

Allergy tablets are similar to allergy shots when it comes to controlling allergy symptoms, and both have been shown to provide long-term improvement even after the treatment has ended. Yet the treatment is only effective for the allergen contained in the shots or tablets. “For instance, if someone is allergic to ragweed and trees, ragweed tablets or shots would only help control ragweed symptoms during ragweed season,” Cox explained. “And while allergy shots can be tailored to include the variety of allergens a person is allergic to, the allergy tablets cannot.”

Allergy tablets have a more favorable safety profile than allergy shots, which is why the tablets do not need to be given in a medical setting after the first dose. However, the FDA-approved product information of the three allergy tablets includes a warning about the possibility of severe allergic reactions and a recommendation that an epinephrine auto-injector be prescribed to patients receiving allergy tablets.

“At the end of the day, it’s important talk to your physician. He or she can determine which option is right for you,” emphasized Cox.