Sublingual immunotherapy (SLIT) — also called allergy drops — does not raise blood sugar and does not interfere with diabetes medications like metformin, insulin, GLP-1 agonists (Ozempic, Mounjaro), or SGLT2 inhibitors. SLIT works locally under the tongue and does not affect glucose metabolism. Most people with type 1, type 2, or prediabetes can safely use SLIT with guidance from their allergist.

Key Takeaways

Will SLIT Affect Blood Sugar or Diabetes Medications?

Quick Answer

No. Sublingual immunotherapy (SLIT) does not raise or lower blood glucose and does not interact with diabetes medications.

Deep Guide

Many adults managing type 1 or type 2 diabetes worry about starting allergy treatment. It makes sense — some medications (like oral steroids or large doses of albuterol) can raise glucose temporarily. So the question naturally comes up:

“Will SLIT affect my blood sugar or diabetes meds?”

Here is the evidence-based breakdown.

1. SLIT works locally under the tongue — not through the bloodstream

SLIT uses micro-doses of allergens placed under the tongue. The allergens interact with immune cells in the oral mucosa and lymph nodes — not through systemic absorption.

Therefore, SLIT does not:

• change insulin sensitivity
• alter glucose metabolism
• stimulate the adrenal system
• impact liver glucose processing
• affect the pancreas

Peer-reviewed studies and AAAAI/ACAAI guidelines confirm that SLIT has no known metabolic effects, including no effect on blood sugar regulation.

2. SLIT has no interaction with diabetes medications

Diabetes medications fall into major categories:

• Metformin
• Insulin
• GLP-1 agonists (Ozempic, Mounjaro, Trulicity)
• SGLT2 inhibitors (Jardiance, Farxiga)
• DPP-4 inhibitors (Januvia)
• Sulfonylureas (Glipizide, Glimepiride)
• Thiazolidinediones (Actos)

None of these have known interactions with SLIT, according to the AAAAI/ACAAI Sublingual Immunotherapy Practice Parameter (2017 update).

SLIT is immune-modulating, not metabolic — so it does not interfere with the way these medications work.

3. Allergy inflammation can actually worsen glucose control

While SLIT itself does not affect blood sugar, uncontrolled allergies can.

Allergic rhinitis and asthma can trigger:

• systemic inflammation
• sleep disruption
• airway stress
• increased use of rescue inhalers
• stress-hormone changes

Chronic inflammation is known to interfere with insulin sensitivity and blood sugar stability.

So improving allergy control through SLIT may actually help with:

• fewer nighttime awakenings
• improved breathing
• better sleep quality
• reduced inflammatory burden

Many adults notice more stable blood sugars once their allergies improve.

4. SLIT is safer for people with diabetes than treatments like oral steroids

Some allergy treatments — such as prednisone bursts — dramatically raise glucose levels.

SLIT is different. It is a controlled, low-dose immunotherapy that avoids systemic steroids altogether.

5. SLIT does not contain sugar or ingredients that affect diabetes

HeyAllergy’s HeyPak® formulas:

• do NOT contain sugar
• do NOT contain glucose-altering compounds
• use minimal glycerin that does not impact blood sugar
• are safe for people with diabetes, metabolic syndrome, or prediabetes

Does SLIT Affect Different Diabetes Medications?

Below is an easy table summarizing any known interaction risks.

Will SLIT Raise or Lower Blood Sugar?

Short answer:

No. SLIT does not raise or lower glucose.

More detail:

Studies show SLIT causes minimal systemic distribution of the allergen extract. The allergen interacts with the mucosal immune system, not the bloodstream.

Therefore, SLIT does not impact:

• fasting glucose
• A1C
• insulin sensitivity
• glucose spikes
• hypoglycemia risk

If your glucose fluctuates on SLIT, it is almost always due to:

• illness
• stress
• changing diet
• fluctuating activity levels
• unrelated medications

Not the allergy drops.

Why Some People Think SLIT Might Affect Blood Sugar

This confusion usually comes from three places:

1. Steroids raise blood sugar — but SLIT is not a steroid

People mix up allergy immunotherapy with steroid treatment.

2. Severe allergies can cause stress-hormone spikes

This can raise glucose levels — but SLIT reduces allergy inflammation.

3. Some people use albuterol more during allergy season

High doses of beta-agonists can raise glucose slightly.

Again, SLIT avoids all these issues.

Why SLIT Is Often a Better Allergy Treatment for People with Diabetes

People with diabetes often prefer SLIT over other treatments because:

• no steroid bursts
• no injections in a clinic
• low risk of systemic reactions
• gentle, consistent treatment
• improves long-term airway inflammation
• improves sleep and energy
• may reduce need for antihistamines or inhalers

SLIT is ideal if you want steady, safe allergy control without glucose swings.

When to See an Allergist (Important Triggers)

You should schedule an online appointment if you experience:

• worsening allergy symptoms despite medications
• year-round nasal congestion
• asthma symptoms during pollen season
• poor sleep due to allergies
• headaches, sinus pressure, or ear fullness
• trouble tolerating steroid medications
• wanting a long-term fix instead of temporary relief

You can book a consultation with a board-certified allergist through telemedicine.

And if you want to start SLIT (allergy drops):
➡️ https://www.heyallergy.com/heypak

What To Do Next (Action Steps)

1. Book an Online Allergy Consultation
A board-certified allergist reviews your symptoms, diabetes history, medications, and goals.

2. Consider Allergy Drops (SLIT)
Custom-mixed SLIT can treat your allergic rhinitis or asthma safely at home.

3. Learn How Telemedicine Works
HeyAllergy offers fast appointments with allergists trained in immunotherapy.

FAQs

1. Can SLIT raise my blood sugar?
‍No. SLIT does not affect glucose, insulin, or metabolic pathways that control blood sugar.

2. Is SLIT safe with metformin, insulin, or Ozempic?
‍Yes. There are no known interactions between SLIT and any diabetes medications.

3. Can allergy flares make diabetes harder to control?
‍Yes. Allergy inflammation and poor sleep can worsen glucose control. SLIT may help stabilize symptoms long-term.

4. Is SLIT safer than allergy shots for people with diabetes?
‍Often yes. SLIT has fewer systemic reactions and avoids steroid premedication.

5. Do SLIT drops contain sugar?
‍No. SLIT formulations do not contain sugar and are safe for people with diabetes.

6. Should I check my blood sugar more often when starting SLIT?
‍Not usually. But if you have brittle diabetes, talk with your clinician for personalized guidance.

Author, Review & Disclaimer

Author: Krikor Manoukian, MD, FAAAAI, FACAAI — Board-Certified Allergist/Immunologist
Bio: Dr. Manoukian is a board-certified allergist/immunologist specializing in telemedicine-enabled allergy care and personalized SLIT programs. He leads HeyAllergy’s clinical team and trains providers in safe immunotherapy.
Medical Review: HeyAllergy Clinical Team (Board-Certified Allergists/Immunologists)
Disclaimer: This article is educational and not a substitute for personalized medical advice. Always consult your clinician about your medications and treatment options.

References

• AAAAI/ACAAI. Sublingual Immunotherapy Practice Parameter Update (2017).
• AAAAI. Ask the Expert: Guidance on medication interactions with immunotherapy.
• NIAID/NIH. Allergic Diseases Research Overview.
• Peer-reviewed literature on sublingual immunotherapy safety and systemic absorption.