Do Allergy Shots Really Work?

Millions of Americans suffer from various types of allergies. Sometimes symptoms are so severe that they become debilitating, interfere with your quality of life, or can even increase your risk of dying from an anaphylactic reaction.

If other treatments have been unsuccessful, you may be considering allergy shots (also called immunotherapy). But do allergy shots really work? Are they worth the risk? Here's what you need to know before choosing immunotherapy.

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Doctor administering shot in the arm
Angela Cappetta / Getty Images.

Testing for Allergens

If you haven't done so already, before starting treatment with allergy shots, your healthcare provider will first run tests to find out the exact substance (or substances) that you are allergic to. If your allergy is a substance in the environment, such as certain types of pollen or pet dander, you may be eligible for allergy shots. Food allergies, however, are not currently treated with allergy shots.

Shots to Desensitize You to Your Allergy Triggers

The substances you are allergic to are called allergens or triggers. Once it's determined what you are allergic to, immunotherapy involves a series of repeated injections of that allergen. The theory is that by exposing your body to the allergen, it will become desensitized to the substance (versus automatically launching the immune response).

So, do allergy shots work? The short answer is yes, but not for everyone. Allergy shots are not a treatment option that should be taken lightly. There are many considerations, including a substantial time commitment, the risk of an allergic reaction to the shots, and the possibility that only some of your symptoms may be cured, or none at all.

While new options are becoming available (such as sublingual drops) that mitigate some of the inconveniences of immunotherapy, these options are still new and not available for everyone.

Build Up and Maintenance

Completing immunotherapy may mean you'll have to go to the healthcare provider's office one or more times per week for several months. The treatment is broken up into two phases called the build-up phase and the maintenance phase. During the build-up phase, you are given increasing amounts of the allergen weekly for three to six months.

The second phase is called the maintenance phase. During the build-up phase, your healthcare provider will determine the best dose of medication (allergen) for you. This is your maintenance dose, which is what you'll receive for the remaining allergy shots and what your practitioner feels you respond to best. The good news is that during the maintenance phase, you will only need to get shots every 3-4 weeks. The maintenance phase lasts about three to five years.


There is always the chance that you could have an allergic reaction to an allergy shot, which could lead to anaphylaxis and even death. However, this is extremely rare, happening once in every 2.5 million doses of immunotherapy administered. It may seem a bit like tempting fate to give someone a substance you know they react to, but you will receive only very small amounts staggered over a long period.

Serious reactions are rare, but you should be sure to undergo immunotherapy only with a qualified allergist/immunologist. These healthcare providers have equipment in their offices for treating allergic reactions.

If you are going to have a reaction to the shot, it will happen within about 30 minutes, so many healthcare providers will have you stay at the office for about a half hour after receiving the shot.

Allergy Shots Don't Always Work

The results of immunotherapy vary widely from one person to another, with some people completely cured and some individuals showing little to no benefit. Almost all patients experience, at the least, a reduction in symptoms. Even if your allergies go away completely, there is always the possibility that they will return, and you will require another round of allergy shots.

Immunotherapy can be a blessing for many people who suffer from allergies, but as you can see, it is not a treatment to be taken lightly. You may wish to ask yourself some of the following questions before making a decision.

  • Do I have the time, and am I willing to spend that time getting allergy shots?
  • Can I afford allergy shots?
  • How many months of the year do my allergies affect me?
  • How serious are my symptoms?
  • Are my allergies decreasing my quality of life?
  • Have I tried other treatments?

If you have not tried other treatments, such as avoiding your triggers or taking antihistamines (such as loratadine or fexofenadine) or other medications to treat allergy symptoms (such as pseudoephedrine or mometasone), try these options before having immunotherapy. However, only you and your healthcare provider can decide if allergy shots are right for you.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Allergy and Infectious Diseases. Treatment for living with food allergy.

  2. Moote W, Kim H. Allergen-specific immunotherapy. Allergy Asthma Clin Immunol. 2011;7 Suppl 1:S5. doi:10.1186/1710-1492-7-S1-S5

  3. Saporta D. Efficacy of sublingual immunotherapy versus subcutaneous injection immunotherapy in allergic patients. J Environ Public Health. 2012;2012:492405. doi:10.1155/2012/492405

  4. The American Academy of Allergy, Asthma & Immunology. Allergy shots (immunotherapy).

By Kristin Hayes, RN
Kristin Hayes, RN, is a registered nurse specializing in ear, nose, and throat disorders for both adults and children.