SLIT for Milk Allergy: What Sublingual Immunotherapy Can and Can’t Do

Sublingual immunotherapy (SLIT) for milk allergy means holding tiny, gradually increasing amounts of milk protein under the tongue to help the immune system react less. In a well-known trial from Johns Hopkins and Duke, SLIT was safer than oral immunotherapy (OIT), where milk protein is swallowed in larger doses, but much less effective: only 1 of 10 children on SLIT alone could eat a large amount of milk protein at the end, compared with 6 to 8 of 10 children who moved on to OIT.

Milk SLIT and OIT are still mostly research treatments. As of October 2026, there is no FDA-approved immunotherapy product for milk allergy; the only approved oral immunotherapy product is for peanut. This guide explains what the evidence shows, the current approved options for food allergy, and what families can do now. For more, see our food allergy guides.

Jump to: Quick answer · About milk allergy · How SLIT and OIT work · What the trial showed · Approved options today · What you can do now · FAQ

Quick answer

• SLIT = small doses under the tongue; OIT = larger doses swallowed. Both aim to raise the amount of milk a person can tolerate.
• Trade-off: in the milk trial, OIT worked better, but systemic reactions (beyond the mouth) were more common with OIT than with SLIT.
• Not a cure: some children who stopped treatment lost their protection within 1 week.
• Approved options: no milk immunotherapy is FDA approved. Xolair (omalizumab) was approved in 2024 to reduce reactions from accidental exposure to foods, alongside avoidance.
• Many children outgrow milk allergy: ACAAI says about 80% are likely to outgrow it before age 16.

About milk allergy

According to the American College of Allergy, Asthma and Immunology (ACAAI), between 2% and 3% of children younger than 3 are allergic to milk. Reactions can include hives, stomach upset, vomiting and, especially in infants, bloody stools. Anaphylaxis is rare but can be life-threatening.

Milk allergy is not the same as lactose intolerance. Allergy is an immune reaction to milk proteins (casein and whey); lactose intolerance is a shortage of the enzyme that digests milk sugar and causes gas, cramps or diarrhea.

How SLIT and OIT work

Both are done under an allergist’s supervision. Doses are increased slowly, often in the clinic, because reactions can happen during treatment.

What the Johns Hopkins and Duke milk trial showed

The study, published in the Journal of Allergy and Clinical Immunology in 2012, enrolled 30 children aged 6 to 17 with milk allergy. All started with SLIT; then they either continued SLIT (up to 7 mg a day) or switched to OIT (up to 1,000 or 2,000 mg a day). After treatment, they were tested with 8 grams of milk protein, roughly what’s in a cup of milk.

• Passed the 8-gram challenge: 1 of 10 in the SLIT-only group, 6 of 10 in the lower-dose OIT group and 8 of 10 in the higher-dose OIT group.
• Safety: the overall reaction rate was similar, but systemic reactions were more common during OIT than during SLIT.
• Durability: when treatment was stopped, 6 of 15 children who had passed lost their protection, 2 of them after only 1 week.

The researchers concluded that OIT was more effective for milk allergy than SLIT alone but came with more systemic side effects.

FDA-approved options for food allergy today

• Peanut OIT (Palforzia): approved by the FDA on January 31, 2020, as the first drug to reduce allergic reactions from accidental peanut exposure. It’s only for peanut allergy.
• Xolair (omalizumab): on February 16, 2024, the FDA approved Xolair to reduce allergic reactions, including anaphylaxis, from accidental exposure to one or more foods in people 1 year and older with IgE-mediated food allergy. It’s an injection, it must be started in a healthcare setting equipped to manage anaphylaxis, and patients must keep avoiding their trigger foods. It’s not for emergency treatment of reactions.

Milk SLIT and OIT aren’t FDA-approved products. Ask your allergist whether milk immunotherapy is available through a study or their practice, and about the risks and the daily commitment involved. Our guide to allergy drops versus shots covers immunotherapy for pollen and dust mite allergies.

What families can do now

1. Avoid milk carefully. ACAAI says avoidance is the main way to manage milk allergy. U.S. law requires packaged foods to declare milk on the label; watch for casein and whey, and note that “may contain” warnings are voluntary.
2. Ask about baked milk. ACAAI notes some people with milk allergy can tolerate milk that has been extensively heated, as in muffins. Only try this with your allergist’s guidance.
3. Keep epinephrine on hand and teach caregivers and teachers how to use it.
4. Check in regularly. Many children outgrow milk allergy, so your allergist may retest over time.
5. Get nutrition help. A dietitian can make sure a milk-free diet still provides enough calcium and other nutrients; see eating well with allergies.

Raw milk is not a safe alternative; see our guide to raw milk and allergies.

This guide is general information, not medical advice. Read our medical disclaimer.

Frequently asked questions

Does SLIT work for milk allergy?

Somewhat, but less than oral immunotherapy. In the main milk trial, 1 of 10 children on SLIT alone passed a large milk challenge, compared with 6 to 8 of 10 who moved on to OIT. SLIT caused fewer systemic reactions.

Is milk immunotherapy FDA approved?

No. The only FDA-approved oral immunotherapy for food allergy is Palforzia, for peanut. Xolair is approved to reduce reactions to foods after accidental exposure, alongside avoidance.

Can a child outgrow milk allergy?

Often, yes. ACAAI says about 80% of children are likely to outgrow milk allergy before age 16, though it takes longer than experts once thought.

Is SLIT safer than OIT?

In the milk trial, systemic reactions were more common with OIT, while overall reaction rates were similar. Both should only be done under an allergist’s care.

Is milk allergy the same as lactose intolerance?

No. Milk allergy is an immune reaction to milk proteins and can be severe. Lactose intolerance is trouble digesting milk sugar and causes digestive symptoms.

Sources

• Keet CA, Frischmeyer-Guerrerio PA, Thyagarajan A, et al. The safety and efficacy of sublingual and oral immunotherapy for milk allergy. J Allergy Clin Immunol. 2012;129(2):448-455.
• American College of Allergy, Asthma and Immunology. Milk and dairy allergy. Reviewed March 21, 2019.
• U.S. Food and Drug Administration. FDA approves first medication to help reduce allergic reactions to multiple foods after accidental exposure. February 16, 2024.
• U.S. Food and Drug Administration. Palforzia. Approved January 31, 2020.

Last reviewed: October 21, 2026.