Allergy shots

Allergy shots are injections you receive at regular intervals over a period of approximately three to five years to stop or reduce allergy attacks. Allergy shots are a form of treatment called immunotherapy. Each allergy shot contains a tiny amount of the specific substance or substances that trigger your allergic reactions. These are called allergens. Allergy shots contain just enough allergens to stimulate your immune system — but not enough to cause a full-blown allergic reaction.

Over time, your doctor increases the dose of allergens in each of your allergy shots. This helps get your body used to the allergens (desensitization). Your immune system builds up a tolerance to the allergens, causing your allergy symptoms to diminish over time.

Why it's done Risks How you prepare What you can expect Results

Allergy shots may be a good treatment choice for you if:

  • Medications don't control your symptoms well, and you can't avoid the things that cause your allergic reactions
  • Allergy medications interact with other medications you need to take or cause bothersome side effects
  • You want to reduce your long-term use of allergy medication
  • You're allergic to insect stings

Allergy shots can be used to control symptoms triggered by:

  • Seasonal allergies. If you have seasonal allergic asthma or hay fever symptoms, you may be allergic to pollens released by trees, grasses or weeds.
  • Indoor allergens. If you have year-round symptoms, you may be sensitive to indoor allergens, such as dust mites, cockroaches, mold, or dander from pets such as cats or dogs.
  • Insect stings. Allergic reactions to insect stings can be triggered by bees, wasps, hornets or yellow jackets.

Allergy shots aren't available for food allergies or chronic hives (urticaria).

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