How Long Do Allergy Shots Last?

Allergy shots can relieve allergy symptoms or make a person “allergy-free” for up to 25 years after treatment ends. However, the treatment itself needs to be administered weekly for about 3 to 5 years to be effective in the long term.

This article explains how long allergy shots last, what happens if you stop abruptly, and how they compare to allergy drops.

At Quello, we offer allergy drops as a suitable alternative to allergy shots for people who value flexibility and convenience in tackling their allergies.

What are Allergy Shots?

Allergy shots, also called subcutaneous immunotherapy, are a type of allergen immunotherapy that involves administering weakened or small doses of the allergens in the form of shots that trigger your symptoms under the skin to decrease your sensitivity to them.

How Long Do You Take Allergy Shots For?

Overall, allergy shots are taken for about 3 to 5 years, depending on how you respond to treatment. However, it is recommended that allergen immunotherapy (both shots and drops) should be taken for around  4 years. (1)

You need to take allergy shots for at least 3 years because it takes time for the body to retrain the immune system to recognize allergens such as pollens, pet dander, or dust mites as harmless, gradually reducing the allergic response over time. 

If allergy shots successfully retrain your immune system to tolerate a specific allergen and promote long-term immune memory, they may significantly reduce or even eliminate allergic reactions to that allergen for up to 25 years or longer after completing a full treatment course. (1)

Allergy testing helps allergy providers target the right allergens, reducing the risk of ineffective or unnecessary treatment. From the results of your allergy testing, your allergy provider can create an allergy treatment specific to that allergen.

Phases of Allergy Shot Treatment

There are two main phases in the allergy shot treatment plan:

Build-up phase - 3 to 6 months:

In this stage, allergy injections are given once or twice per week. Your doctor will increase the amount of allergen in your shots weekly for about 3 to 6 months to build your allergy tolerance. You may notice that your symptoms decrease during the build-up phase (2).

Maintenance Phase -up to 3 to 5 years :

Once you reach your effective dose, that is the highest dose your body can tolerate without side effects and is strong enough to retain your immune system, your allergy shot provider will switch to a maintenance dose.

In the maintenance phase, your dose will no longer be increased, and there will also be longer periods between your allergy treatments. You may be required to come in every two to four weeks rather than weekly, but your allergist will decide how often you need to come in.

It may take up to 12 months on the maintenance dose to notice a significant improvement in how you react to allergies. However, you may need to continue your maintenance treatment for about 3 to 5 years. (2)

How Long Does the Effect of an Allergy Shot Last?

The effect of allergy shots can last decades, depending on how long your treatment lasts and how you respond to therapy.

If you take your allergy shots as recommended (for 3 to 5 years), evidence shows that they change your immune system, and the allergy relief is sustained for at least 2 to 3 years after you stop treatment. (3) That said, some patients report being allergy-free for decades or even longer.

However, if your immunotherapy treatment was shorter than 3 years, studies suggest that you may relapse to your previous symptom level, one year after stopping your allergy shots. (3) If you need to stop allergy treatment, talk to your allergy provider.

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Allergy Shots vs Allergy Drops

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Take Control of Your Allergies at Home with Quello Allergy Drops

If you’re looking for a more convenient and flexible way to reduce your allergy symptoms or if you’re uncomfortable with needles, allergy drops may be a suitable alternative.

To get started with Quello, take our free allergy test to identify your triggers, then speak with one of our consultants to review your results and create a personalized treatment plan.