Common causes of hypokalemia include inadequate dietary consumption of potassium, severe diarrhea, improperly managed diabetes, extremely low - calorie diets, excessive sweating, chronic alcoholism, vomiting, Crohn's disease, some heart medications, diuretics and laxative use. (healthyeating.sfgate.com)
This kind of condition is known as hypokalemia. (pandavita.com)
Some cats are prone to muscle disease (myopathy) and a few special cats muscle inflammation (eg hypokalemia in Burmese cats, and myopathy in Sphynx cats). (2ndchance.info)