Getting enough
A ration with at least 50% roughage generally meets potassium needs, including for working horses; hard work may double the requirement [1]. Potassium is also lost in sweat, at about 2 g per litre [1].
Too much
Concentrated potassium salts that are absorbed quickly can cause acute hyperkalaemia and potentially fatal heart arrhythmias, so large forced doses should be avoided [1].
HYPP
For horses with hyperkalaemic periodic paralysis (HYPP), the MSD Veterinary Manual recommends keeping total dietary potassium at or below 1% of the diet. Soaking forage leaches out potassium along with water-soluble sugars [1].
Sources
- 1. Liburt NR (peer reviewed by Boyle AG). Nutritional Requirements of Horses and Other Equids. MSD Veterinary Manual, Professional Version. Merck & Co., Inc., Rahway, NJ. Last full review February 2026. https://www.msdvetmanual.com/management-and-nutrition/nutrition-horses/nutritional-requirements-of-horses (accessed 2026-11-07)
Last edited 7 Nov 2026, 1:48 am