Potassium is an essential electrolyte for proper muscle function. However, high blood potassium levels cause a life-threatening condition known as hyperkalemia.

Langdon Fielding, DVM, Dipl. ACVECC, ACVSMR, of the Loomis Basin Equine Medical Center, in Penryn, California, summarized treatment options at the 2016 American Association of Equine Practitioners Convention, held Dec. 3-7 in Orlando, Florida.

Causes of Hyperkalemia

The two main causes of hyperkalemia include failure of the kidneys to remove potassium (which gets excreted in the urine) and abnormal potassium release from cells. Horses with a history of hyperkalemic periodic paralysis (HYPP, a genetic muscle disorder of Quarter Horses), compromised kidney function, or massive cellular damage (due to injury or disease) are at greater risk of developing hyperkalemia, said Fielding.

Signs of Hyperkalemia

Muscle weakness is a classic sign of hyperkalemia and, while on its own it’s a fairly general symptom, when accompanied by changes in cardiac rhythm, veterinarians should suspect hyperkalemia. Cardiac changes are not always present in hyperkalemia cases, Fielding noted to veterinarians, so don’t rule out a diagnosis in the absence of such abnormalities