🚫 Vet Guide: Why Previcox Is Not for Horses | 2025 Legal, Safety & FDA Medication Use Rules 🐶🐴

By Dr Duncan Houston, BVSc

When it comes to treating arthritis and inflammation in horses, many owners look for ways to reduce costs. One common shortcut? Using **Previcox**, a drug made for dogs, instead of the equine-approved **Equioxx**. But while both products contain the same active ingredient—**firocoxib**—substituting one for the other in horses is **illegal** and can pose risks. 🚫💊

In this 2025 guide, I’ll explain the regulations surrounding veterinary medications, why drug approvals matter by species, and why **only Equioxx is safe and legal for equine use**. 🧠⚖️

💡 Firocoxib: One Drug, Two Products

Firocoxib is a **non-steroidal anti-inflammatory drug (NSAID)** used to relieve pain and inflammation associated with **osteoarthritis** in both dogs and horses. 🧬

Product Differences:

• 🐶 **Previcox** – FDA-approved for **dogs only**
• 🐴 **Equioxx** – FDA-approved for **horses only**

Although the **active ingredient is the same**, the **dosages, formulations, testing protocols, and FDA approvals are not**. That distinction is critical from a legal and safety standpoint. ⚠️

⚖️ Why You Can’t Use Previcox in Horses

In veterinary medicine, using drugs across species is regulated under the **Animal Medicinal Drug Use Clarification Act (AMDUCA)**. This law allows veterinarians to use drugs off-label in certain situations, but only within specific limits. 📜

Key Rules Under AMDUCA:

• 💊 A vet may prescribe a **human drug** for an animal if no approved animal version exists
• 🐴 A vet **may not prescribe an animal drug from another species** if an approved version for the target species exists
• ⚖️ Cost is **not** a legal justification for using an unapproved species-specific drug

So even though Previcox and Equioxx contain the same compound, **Previcox is not approved for horses**, and using it violates FDA regulations. ❌

📉 Why the Price Difference Exists

Many owners are frustrated by the price gap between Previcox and Equioxx. But this difference reflects the **extensive research, safety trials, and regulatory processes** required to get a drug approved for horses. 🧪

Horses are more costly to test than dogs due to their size, biology, and specialized care needs during clinical trials. These added expenses contribute to the higher cost of Equioxx. 💸

While frustrating, these protections exist to ensure **safety, efficacy, and dosage precision**—all crucial for your horse’s health. 🧠

⚠️ The Risks of Using Previcox in Horses

• 💉 Incorrect dosing due to species differences in metabolism
• 🧪 Lack of safety data in equines using the dog formulation
• ⚖️ Legal liability for owners and vets who prescribe off-label illegally
• 🚫 Potential for adverse reactions, reduced effectiveness, or overdose

It’s not just about saving money—it’s about protecting your horse with medications that have been tested and proven **safe for their species**. ✅

📱 Use Ask A Vet to Choose Safe Equine Medications

The Ask A Vet app helps you navigate prescription choices the safe and legal way:

• 📋 Ask about alternatives to Equioxx for managing arthritis
• 🧠 Get expert input on legal off-label options when needed
• 💊 Track pain management protocols safely
• 📱 Ask questions before purchasing meds from online sources

Don’t take shortcuts when it comes to your horse’s care. 🐴📲

✅ Key Takeaways for 2025

• 💊 Firocoxib is used in both Previcox (dogs) and Equioxx (horses)
• ⚖️ Previcox is **not approved for equine use** and is illegal to prescribe for horses
• 🧪 Species-specific testing ensures safety and proper dosage
• 📉 Using Previcox in horses can lead to health risks and legal consequences
• 📱 Use Ask A Vet to explore safe and effective arthritis treatments

📲 Final Thoughts from Dr Duncan Houston

When it comes to medication, **cheaper doesn’t mean safer**. While Previcox and Equioxx share a name and active ingredient, only one has been tested and approved for use in horses. Trust your vet, follow the law, and **treat your horse with confidence** using the right tools for their species. 🧠💙

Download the Ask A Vet app to get help with equine prescriptions, safe alternatives, and medication advice tailored to your horse’s condition. 🐎📱