Vet Guide 2025: Griseofulvin for Horses 🐎

I'm Dr Duncan Houston BVSc, your caring veterinarian, here to provide an in-depth 2025 guide on griseofulvin in horses: its role, dosing, safety, and best practices—all with warmth, clarity, and actionable steps.

1. 🧪 What Is Griseofulvin?

Griseofulvin is a prescription antifungal targeting dermatophytosis (ringworm) in horses. It’s FDA-approved for equine and canine use and helps prevent fungal spread across skin and coat :contentReference[oaicite:2]{index=2}.

2. How It Works in Horses

Instead of killing fungus directly, griseofulvin stops fungal cell division and embeds in keratinized tissue, reducing contagiousness and accelerating recovery :contentReference[oaicite:3]{index=3}.

3. When & Why It's Used

Horses with ringworm or rain rot may benefit from oral griseofulvin, though topical treatments might be preferred in mild or localized cases :contentReference[oaicite:4]{index=4}.

4. Dosing & Administration 🩹

• General dose: 5–10 mg/kg once daily for 3–6 weeks; foals may receive ~15 mg/kg for 2–4 weeks :contentReference[oaicite:5]{index=5}.
• Administer with a fatty treat (e.g., oil or fat-rich feed) to increase absorption.
• Wear gloves when handling; pregnant handlers must take precautions :contentReference[oaicite:6]{index=6}.
• Missed dose? If not near the next schedule, give when remembered; otherwise, skip—never double-up :contentReference[oaicite:7]{index=7}.

5. Possible Side Effects ⚠️

Generally well tolerated in horses. Potential effects include:

• GI upset: decreased appetite or diarrhea
• Depression/low energy
• Red blood cell suppression—rare anemia cases
• Liver irritation

For humans, accidental ingestion or contact can be harmful; pregnant people should avoid exposure :contentReference[oaicite:8]{index=8}.

6. Monitoring & Safety Checks

• Perform fungal cultures to confirm progress.
• Run bloodwork (CBC, liver enzymes) every 1–3 weeks during treatment :contentReference[oaicite:9]{index=9}.
• Stop treatment and call your vet if severe side effects occur or no improvement after several weeks.

7. Handling & Human Safety

• Use gloves—avoid inhaling dust.
• Pregnant or potentially pregnant individuals should not handle the medication :contentReference[oaicite:10]{index=10}.
• If ingested by humans, seek medical advice or Poison Control at 800‑222‑1222.

8. Environmental Management

Ringworm fungi produce long-lasting spores—up to 18 months. Implement rigorous disinfection of equipment, stalls, tack, grooming tools, and bedding. Isolate infected horses until cultures are negative.

9. Comparisons & Alternatives

When possible, veterinarians may prefer topical therapies. However, oral griseofulvin shines in widespread infections or when topicals aren't feasible. In horses, systemic treatment is limited to griseofulvin among FDA-approved options :contentReference[oaicite:11]{index=11}.

10. When to Contact Your Vet

• Severe GI signs, lethargy, or incoordination
• Signs of anemia, jaundice, or bleeding
• No improvement within 3–4 weeks
• Accidental human exposure or overdose

11. Ask A Vet & Partner Services

At Ask A Vet, we provide:

• 💬 Vet chat for dosing and side‐effect guidance
• 📚 Support on compounding (pastes, powders)
• 🧴 Recommendations for topical, stall, and tack disinfectants
• 🏇 Advice on activity adjustments while healing

12. Quick Reference Table

13. Final Thoughts ❤️

Griseofulvin remains a trusted systemic antifungal for horses in 2025. With responsible dosing, monitoring, and hygiene, most horses respond well. At Ask A Vet we’re here to support your horse’s healing journey with expert advice and supplementary care options. 🐴

Call to Action 📲

For personalized guidance on griseofulvin use, fungal clearance, stall disinfection, or supportive therapies, visit AskAVet.com or download the Ask A Vet app today—your partner in equine health and peace of mind.