I was woundering could you still ride
a horse that has heaves?
would depend on how bad the case of heaves is and how hard the horse is ridden.
horse with mild heaves that is being properly managed might be able to be used
horse with severe heaves, even with proper management, might not be able to be
ridden at all.
Please confer with your veterinarian
about this. But in the meantime, to read more about heaves, go here: Heaves.