How Do Allergy Shots Work?

Allergy shots contain tiny amounts of allergens (such as pollen, mold, cat or dog dander, etc.). We give these shots in a customized combination tailored for your specific allergies. For instance, if you're allergic to insect stings, allergy shots will lower your chances of having a dangerous reaction to another insect sting in the future. 

Allergen immunotherapy is another term we use to describe allergy shots because the injections change the way your immune system reacts to allergens (substances that you are allergic to). Some studies have shown that it may play a role in preventing asthma from developing in some patients with allergic rhinitis. 

Candidates for Allergy Shots

Allergy shots are injections that we prescribe for pediatric and adult patients with the following conditions:

  • allergic rhinitis (hay fever),
  • allergic asthma,
  • atopic dermatitis (eczema), or
  • insect sting allergies. 

We typically recommend allergen immunotherapy for people with moderate or severe allergic symptoms that can’t be controlled by medications or changes to their environment.

Types of Allergy Shots

Allergy shots are available for environmental and venom allergies.

These shots treat people with the following allergies:

  • pollen (tree, grasses, and weeds);
  • animals (commonly cats and dogs, but other animals may be considered);
  • mold;
  • dust mites;
  • cockroaches; and
  • stinging insects (bees, yellow jackets, hornets, wasps, and fire ants).

How Often Do You Get Allergy Shots?

We administer allergy shots in two phases: the build-up phase and maintenance phase.

Build-Up Phase

You will start receiving injections once each week. In some cases, we may give the shots more frequently. As time goes on, we will gradually increase the amount of allergens in your injections. The duration of this phase lasts for three to six months. However, this time frame largely depends on the injection frequency.

Maintenance Phase

This phase begins when you have reached a dose that effectively improves your allergic symptoms. The maintenance dose is based on your degree of sensitivity (how allergic you are) to the allergens in the vaccine and your response to the immunotherapy build-up phase. Once we reach the ideal  maintenance dose, we will start to increase the time between your allergy injections.

You will typically receive these injections once every four weeks. However, this time span may vary from person-to- person. Some people benefit from shorter intervals between allergy injections while others may tolerate injection intervals longer than four weeks. Our goal is to provide the best combination of effectiveness and safety for each patient undergoing allergy shot treatments.

Find an Allergy Specialist

Allergy Shot Effectiveness

Allergy shots may decrease the severity of your allergic reactions to common allergens such as pollen, mold, animal dander, and dust mites. For most people, the initial six to 12-month course of allergy shots will gradually decrease their sensitivity to airborne allergens. As patients continue their injections, their symptoms will improve and they will need less medication.

It's important to administer your shots at the same time interval (about once a week). It's okay if you miss your shots here and there. However, waiting too long (more than two weeks for the build-up phase and more than five weeks for the maintenance phase) in between injections may require your allergist to adjust the shot dosage.

What to Expect at Your Appointment

You should take an oral antihistamine such as cetirizine (Zyrtec), fexofenadine (Allegra), or loratadine (Claritin) on the morning of your allergy shot appointment or right before coming to your appointment. However, only do so if it's okay to take these medications alongside your allergy shots. If you are unsure, ask your allergist.

Once you check in at the front desk for your appointment, a member of our clinic staff will bring you to an exam room. He or she will ask you some questions to evaluate you for any active asthma symptoms before administering your shot. 

You will typically receive one to four injections depending on your allergies. We will place the needle into your upper arm to inject the allergen into the tissue between your skin and muscle. Then we will monitor you in the clinic for 30 minutes. It's common for people to experience itching and swelling at the injection site from the allergy shots. If this occurs, we will apply hydrocortisone cream to provide some relief.

Allergy Shots Cost

Allergy shots are usually covered by most insurance plans. If you are a candidate for allergy shots, our team will help you obtain insurance coverage information.

Allergy Shots: Side Effects & Reactions

It's possible to have an allergic reaction to the allergy injection itself. Reactions may be local (swelling at the injection site) or systemic (affecting the rest of the body).

Systemic reactions may include:

  • hay fever-like symptoms (runny nose, watery eyes, congestion, and sneezing),
  • hives,
  • flushing of the skin,
  • lightheadedness,
  • asthma, and
  • rarely, life-threatening reactions.

Serious systemic reactions may occur in patients with worsening asthma or asthma that's not controlled well on medications. If you have noticed worsening asthmatic symptoms, notify your nurse or dermatologist immediately before receiving your scheduled injections.  

Heavy exposure to pollen during pollen season and exercise after an injection may also increase your risk for allergic reactions to the injections. However, allergic reactions to the injections may occur even in the absence of these conditions. 

How Long Do Allergy Shots Last?

People who receive allergy shots over a three to five-year span will see a huge improvement in their allergic symptoms for years after discontinuing their shots. Keep in mind that it is still possible for your allergic symptoms to relapse. We will start immunotherapy again for any patients who experience a relapse in their allergic symptoms.

How to Make an Appointment with Our Allergy Specialists

To schedule an appointment call 801-581-2955 or submit an appointment request. A referral is not required to meet with our allergy specialists. However, you may want to verify your coverage with your insurance carrier first as some carriers do require a referral from a primary care provider to be seen by a specialist.

If you are transferring from another practice to U of U Health for allergy care, you will need to be evaluated by one of our providers before starting your allergy shot regimen at our clinic. 

Virtual Allergy Visits

Our allergy specialists also offer safe and easy virtual appointments. Our virtual care system allows us to evaluate and treat you via videoconferencing from the comfort of your home.

Learn How to Set Up a Virtual Visit

Sign Up for Our Newsletter