Health Library

Health Library Explorer
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A-Z Listings
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Click a letter to see a list of conditions beginning with that letter.
Click 'Topic Index' to return to the index for the current topic.
Click 'Library Index' to return to the listing of all topics.

Allergy Shots (Immunotherapy)

Many people take medicines and stay away from their triggers to control their allergies. Allergy shots (immunotherapy) are another type of treatment that can give long-term relief of allergy symptoms. The goal of the treatment is to make your body less sensitive to allergens. Allergens are the substances that cause your allergies. Allergy shots can treat allergies to things such as dust mites, cats, dogs, pollen, and some insect stings.

The shots work by helping your body gradually get used to the allergens. Then your immune system no longer responds to allergens as if they were harmful. You will have allergy testing to figure out what your allergens are before having allergy shots. This testing will help your healthcare provider decide what to include in your allergy shots.

Health care provider giving shot in girl's upper arm. Woman standing in background.

What are allergy shots?

Each allergy shot contains a small dose of the substances that cause your allergies. The dose is slowly increased as your treatment continues. You’ll get shots once or twice a week at first. After about 3 to 6 months you will reach your maintenance level. Then you will get shots every 2 to 4 weeks. Your allergy shots may continue for a few years or even longer. It's important to stay on schedule. This gives the shots the best chance to work. And it helps you get to your maintenance dose and schedule sooner.

Immunotherapy to treat insect sting allergies is called venom immunotherapy (VIT). It treats allergies to stings from insects, such as honeybees, wasps, yellow jackets, and hornets. A small amount of venom is used in the treatment. Your healthcare provider may advise these shots if you have had a severe reaction (anaphylaxis) to a sting in the past. VIT helps reduce the risk for a severe allergic reaction happening again.

Deciding to have allergy shots

When deciding if you should have allergy shots, you and your healthcare provider should think about the following:

  • How long your symptoms last each allergy season, or if you have symptoms all of the time

  • How severe your allergy symptoms are

  • If taking medicines and preventing triggers helps you

  • If you want to keep taking allergy medicine

  • Time and cost of allergy shots

Getting your shots

Allergy shots are given by injection in the upper arm. You may have 1 or more shots. The number depends on how many things are causing your allergies. You may feel a slight sting when you get each shot.

After your shots

After your shots, you’ll need to wait for 30 minutes before you can leave. This is to make sure you're not having a serious reaction to the shot. You may have itchiness and soreness in your arm. Or you may have sneezing and a stuffy nose. If you have a serious reaction, you'll receive treatment while you’re in your provider's office. Some people can have swelling at the site of injection a few hours after their injection. This is typically not a sign of a severe reaction. But let your allergy specialist know about these reactions. They may adjust the dose of your next shot.

What is a serious reaction?

In rare cases, allergy shots can cause a reaction called anaphylaxis. These rarely occur more than 30 minutes after you have received your shot. This is a life-threatening problem that must be treated right away. Most people who get allergy shots will be prescribed an epinephrine autoinjector by their healthcare provider. If you have any of the symptoms below, use your epinephrine autoinjector and call 911:

  • Swelling in your throat

  • Wheezing or chest tightness

  • Trouble breathing

  • Feeling dizzy or lightheaded

Online Medical Reviewer: Dan Brennan MD
Online Medical Reviewer: Marianne Fraser MSN RN
Online Medical Reviewer: Rita Sather RN
Date Last Reviewed: 3/1/2024
© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.