Horse Side Vet Guide ®

Equine Health Resource

Re-Feeding Syndrome

Horses that are severely underweight require careful dietary management, as it may take many months for a horse to return to a healthy weight and condition.

Re-feeding syndrome is a life-threatening electrolyte imbalance that is caused by an (often well-intended) attempt to put weight on a starved or severely emaciated horse.

Horses that have been starved are extremely fragile. Their digestive tract does not produce adequate enzymes or contain a healthy bacterial population for digestion.

A drastic increase of carbohydrates or glucose causes insulin levels to rise, which shifts the mineral balance that can result in kidney, heart and respiratory failure.

Prognosis & Relevant Factors

Guarded to good, depending on promptness of treatment and the overall health of the horse.


Talk to your vet about how to safely bring your horse up to its proper weight and body condition.

All dietary changes must be made gradually over several months to ensure success.

Helpful Terms & Topics in HSVGWritten, Reviewed or Shared by Experts in Equine Health

Helpful Outside ResourcesCredible Equine Health Information on the Internet

Author: Doug Thal DVM Dipl. ABVP


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