Allergy Immunotherapy: Shots, Tablets, and Long-Term Relief

Allergy immunotherapy teaches the immune system to quit overreacting to pollen, mold, and other triggers. It is the only treatment that changes the underlying allergy instead of masking symptoms, and it can stop new allergies and asthma from developing (per ACAAI).

The therapy comes in two forms: allergy shots, the most common and most effective, and sublingual tablets. A full course lasts 3 to 5 years. Around 80% of users gain marked relief, and about 60% hold onto that benefit after therapy ends.

How well immunotherapy works

Allergy shots are the only disease-modifying treatment — they retrain the immune system rather than masking symptoms.

Symptom improvement80%

ACAAI — most patients improve on a full course

Lasting benefit after stopping60%

ACAAI — benefit that persists after a completed course

Share of patients who benefit. Source: ACAAI.

How allergy shots work

Allergy shots, called SCIT, feed the body rising, measured doses of the exact allergens that bother you. During the build-up phase you receive one to three injections a week for roughly 6 to 10 months, then move to maintenance shots about once a month for a total of 3 to 5 years. Because a serious reaction is possible, every injection is given in an allergist's office followed by a 30-minute observation period.

Sublingual tablets

Sublingual immunotherapy, or SLIT, is a tablet held under the tongue for a minute or two before swallowing. Only FDA-approved tablets in the US cover ragweed, northern pasture grasses such as timothy, and dust mites. Allergy drops are a separate product that is not FDA-approved, is off-label in the US, and is usually not covered by insurance (per ACAAI).

Who is a candidate

Immunotherapy suits people whose symptoms stay poorly controlled despite medication and avoidance, those carrying a heavy pill load or side effects, or anyone who wants to quit daily medication. The AAO‐HNSF 2015 guideline advises offering or referring for immunotherapy when allergic rhinitis fails to respond to drugs. An allergy test first pinpoints what to target. Children can begin therapy too, which may stop years of worsening symptoms before they settle in.

What to expect

Immunotherapy is measured in years, not weeks, and gains appear step by step. The reward is durable: around 80% improve markedly and about 60% keep lasting benefit after completing a 3-to-5-year course. Because it can block new sensitivities and blunt progression toward asthma, it is the one allergy treatment that actually changes the disease.

Shots and FDA-approved tablets are generally covered by insurance, unlike off-label allergy drops, so they remain the standard route. Missing doses slows progress, so the people who benefit most are those who can stick to the full schedule. For them, a few years of therapy can replace decades of daily medication.

What a course involves

3–5years

typical full treatment course

ACAAI

6–10months

build-up phase before maintenance

ACAAI

30min

in-office wait after each shot

Cleveland Clinic

Check your local pollen forecast

Pollen seasons vary sharply by region. These metros see some of the worst pollen pressure — check the current forecast for each, or look up any US city on the pollen count hub:

Frequently asked

What is allergy immunotherapy?
A treatment that gradually exposes you to your allergens so the immune system stops overreacting. It is the only option that changes the underlying allergy and can prevent new allergies and asthma.
How long do allergy shots take?
A build-up phase of one to three shots a week lasts about 6 to 10 months, then monthly maintenance continues for a total of 3 to 5 years.
How well do allergy shots work?
About 80% of people see significant symptom improvement, and roughly 60% keep lasting benefit after completing a 3-to-5-year course.
What is the difference between shots and tablets?
Shots (SCIT) are given in the office and treat many allergens. Sublingual tablets (SLIT) are taken at home but are FDA-approved only for ragweed, grasses, and dust mites.
Are allergy shots safe?
They carry a small risk of a serious reaction, so they are given in an allergist's office with a 30-minute observation period afterward. Serious reactions are uncommon.
Who should consider immunotherapy?
People whose allergies are not controlled by medication and avoidance, who have a heavy medication burden, or who want to stop relying on daily pills. An allergy test confirms what to target.

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