Prognosis
For mild to moderate cases of ER, the prognosis is excellent, with the horse successfully returning to its former level of competition. However, if the vet's recommendations for preventing ER are not followed, ER may likely recur.
Horses who experience a severe case of ER (the muscle degeneration is significant) are less likely to return to their previous level of competition, as fibrosis may have occurred, which would result in loss of muscle function. The prognosis is guarded for these horses.
Read more about this topic: Equine Exertional Rhabdomyolysis