🐾 Vet-Approved 2025 Guide: Immunotherapy for Allergies in Cats, Dogs & Horses—What to Expect 🐶🐱🐴💉

By Dr. Duncan Houston, BVSc

Does your pet suffer from recurring itching, ear infections, or skin irritation? If airborne allergies are to blame, Allergen-Specific Immunotherapy (ASIT)—commonly known as allergy shots—may be the most effective long-term solution 🧪🌿

Unlike medications that only suppress symptoms, ASIT works with your pet’s immune system to reduce the allergic response over time. It’s effective for cats, dogs, and horses and has the potential to significantly improve quality of life 💉🐾

🔬 What Is Immunotherapy?

ASIT involves injecting or administering small amounts of allergens (pollens, dust, molds) that the pet is allergic to. Gradually, their immune system becomes desensitized to these triggers. Over months, the allergic response weakens—sometimes permanently 🧠🛡️

Key Points:

• ✅ Effective in ~75% of pets
• ⏳ Takes 6–12 months to evaluate effectiveness
• 🔁 Ongoing treatment is often needed but with fewer meds

🚫 Not for Food Allergies

Food allergies must be diagnosed and treated with a strict diet trial. ASIT does not work for food-related symptoms 🍽️❌

🧪 Allergy Testing First

Allergy testing determines which substances should go into your pet’s serum. It doesn’t diagnose “if” your pet has allergies—but what they’re allergic to.

Testing Options:

• 🧴 Intradermal Skin Testing (IDST): Done by dermatologists, involves shaving and injecting allergens into the skin
• 🩸 Blood Testing (In Vitro): Looks for IgE antibodies in the blood; no medication withdrawal needed

🧠 Many dermatologists use both to craft the best treatment serum.

💉 Administering Allergy Shots

• 📈 Doses start small and gradually increase over weeks
• 💪 Maintenance shots are usually given every 2–3 weeks
• 🏥 Can be given at home or in a vet’s office

⚠️ Watch for Rare Reactions:

• 😰 Facial swelling or hives
• 🤢 Vomiting or diarrhea
• 😴 Listlessness or injection site swelling

Stay with your pet for 30–60 minutes after each injection and report any reactions before the next dose 🐾

💊 Alternatives to Injections

1️⃣ Rush Immunotherapy

• 🚀 12 injections over 6 hours under close supervision
• 🧪 Fast-tracks your pet to maintenance doses
• ⚠️ Slightly higher risk of reaction—done in clinic only

2️⃣ SLIT (Sublingual Immunotherapy)

• 💧 Liquid drops placed under the tongue
• 📆 Given once or twice daily
• ✅ Great for pets that don’t tolerate needles
• 🛑 Must not be mixed with food and cannot be swallowed immediately

🧠 Who Benefits Most?

Allergen immunotherapy is best for:

• 🐶 Dogs and 🐱 cats with atopic dermatitis (airborne allergy)
• 🐴 Horses with seasonal itching or hives
• 📉 Pets needing long-term relief without heavy medications

📈 What to Expect Over Time

• ⏳ It can take 6–12 months to see improvement
• 📉 Flare-ups may reduce in severity and frequency
• 📋 Regular rechecks help adjust the protocol

📲 Ready to Explore Allergy Immunotherapy?

If your pet suffers from chronic itch, rashes, or recurring skin and ear infections, ask your vet about ASIT. For second opinions or specialist help, visit AskAVet.com or download the Ask A Vet app 📱

🌿 With time and the right plan, your allergic pet can experience relief—naturally and safely 💉🐾