Information about Immunotherapy

If you suffer from the drippy nose and itchy eyes of chronic or seasonal allergies, you've probably filled your medicine cabinet with medications to reduce your discomfort: antihistamines to block the body chemicals that cause allergic reactions, and steroid sprays and decongestants that reduce nasal swelling and mucus production. But allergy shots—known in doctor-speak as subcutaneous immunotherapy (SCIT)—are the only proven therapy that can get at the underlying cause of your misery.

The goal is for weekly injections of increasingly larger doses of substances that trigger allergic reactions to eventually desensitize you. You may get some relief within a few months, and can start getting shots less frequently once you've reached your top (or maintenance) dose. Reaching the top dose can take as little as a year, though three years is common; you'll likely continue treatment for a total of three to five years.

How well does immunotherapy work?

After just one year, people can have a 60 to 80 percent improvement in symptoms, says allergy specialist Harold Nelson, M.D., a professor of medicine at National Jewish Health hospital in Denver. "After three or four years, most people have gone from the point where they were miserable from their allergies despite taking antihistamines to the point where they don't need antihistamines at all."

The benefits of immunotherapy may go beyond allergy relief. There's evidence that immunotherapy can prevent someone with allergic rhinitis from developing asthma—a common occurrence, says Linda Cox, M.D., president-elect of the American Academy of Allergy, Asthma & Immunology (AAAAI).

Another perk is the savings. Immunotherapy has been shown to be more cost-effective than other allergy treatments.

Will allergy shots work for me?

Visiting your allergist on a regular basis for years is quite a commitment, so if you have only occasional bouts with allergies, immunotherapy is probably not the best use of your time and co-pays. Immunotherapy is also not for kids under age five; if you're elderly, pregnant, have a cardiac condition and/or are taking beta-blockers, discuss options with your physician.

Before you start immunotherapy, you also need to know whether it will help with your particular allergies. So far, this treatment has proven helpful in treating seasonal and household allergies such as pollen, dust, mold and pet dander. It can also treat insect venom allergies, but is only recommended if your reactions to venom are potentially severe—such as trouble breathing, drop in blood pressure and/or fainting.

When it comes to food allergies, recent research is quite promising. In a study from the New England Journal of Medicine, for example, 55 children with egg allergy were given increasing amounts of egg-white powder by mouth over three years. After 22 months, 75 percent were able to ingest small amounts of egg white powder and manage occasional exposure to eggs with fewer symptoms. At the three-year mark, 28 percent of the youngsters were able to eat eggs as often as they pleased with no side effects.

Peanut allergies may also respond to immunotherapy. A small study conducted by the Allergy & Respiratory Research Group in the U.K. on 28 children with peanut allergies found that after one year, all the youngsters who had been exposed to increasing doses of peanut product were able to eat the equivalent of 20 peanuts without symptoms. Still, according to the National Institute of Allergy and Infectious Diseases (NIAID), more information on safety and efficacy is needed before immunotherapy is made available for treatment of food allergies.

If you feel you can't wait for seasonal allergy relief, ask your allergist about cluster immunotherapy. Here, you go for multiple injections twice a week for four weeks to reach top dose, then stay on monthly maintenance injections for the typical three to five years. "With cluster, you get to a maintenance dose in eight visits, as opposed to at least 24 to 30 visits for conventional therapy," says Dr. Cox.

An even more rapid approach for seasonal and household allergies is rush immunotherapy. With this, you receive increasingly larger doses of allergens over the course of one to three days, while your doctor monitors you closely. After you reach your top dose, you receive maintenance shots once a month for the usual three to five years. With rush, results can be fast—studies indicate that people typically display fewer allergy symptoms on the very first day.

Accelerated therapies, says Richard Weber, M.D., president of the American College of Allergy, Asthma and Immunology (ACAAI), offer "more flexibility, faster results and a treatment plan people are more likely to follow because it reflects their needs and busy lifestyles." Some experts, however, have concerns about rush therapy. The potential problem, says Dr. Cox, is that anaphylaxis—a severe allergic reaction that may include hives, difficulty breathing, wheezing, swelling of the tongue, throat and nose, dizziness and nausea—can be more common with the sped-up schedule (up to 38 percent, even if your doctor pre-treats you with antihistamines or steroids), while cluster and traditional immunotherapy have a very low risk (less than one percent) of this type of reaction. People with severe allergic reactions to insect venom, however, seem to get more relief—with no more safety risks—from single-day therapy.

Allergy Shots: Help for Asthma?

If you, like 50 percent of adults with asthma, find that allergies set off your breathing problems, immunotherapy can help. Often, controlling the allergies will help minimize asthma symptoms as well. But be sure to mention your asthma to the allergist on your initial visit, cautions Dr. Weber. "Severe side effects of immunotherapy are rare, but can take the form of trouble breathing in people with asthma—as opposed to the hives and high blood pressure you might see in someone else."

In addition, if your asthma symptoms have flared up in the three days before an immunotherapy treatment, let your allergist know. You may need to skip a dose of immunotherapy to minimize your risk.

Whether or not you decide to go the immunotherapy route, take smart lifestyle steps to minimize the likelihood of an asthma episode. If you have allergic asthma, air purifiers with HEPA filters can help reduce allergens such as pollen and pet dander, according to Dr. Weber. It's also wise to opt for hardwood floors instead of carpet and to use a vacuum that has a HEPA filter.

And, if you use a humidifier to relieve sinus symptoms, you may want to pull the plug. "As soon as you turn a humidifier on, the mold spore count in the air rises," says Dr. Weber. "With a whole-home humidifier, you're recirculating allergens in the vents back through your home."

Most importantly, follow your doctor's recommendations. Work with your doctor to write an action plan. This should contain instructions on what medications to take and when, what to do in case of a flare-up, how to monitor your asthma properly and a list of what triggers your symptoms. And follow the plan: take your medications and keep an eye on your respiratory health as directed.

Source: From our sister publication Remedy's Healthy Living Spring 2013

Publication Review By: the Editorial Staff at Healthcommunities.com

Published: 21 Feb 2013

Last Modified: 24 Feb 2015