Feline Hypokalaemia

What is hypokalaemia?

Hypokalaemia is a term that refers to low blood concentrations of potassium. Potassium is an important electrolyte (chemical) within the body and is very important for the normal function of muscles and nerves. Hypokalaemia is the most common cause of generalized muscle weakness in cats.

What are the clinical signs associated with hypokalaemia?

Mild to moderate hypokalaemia is seen relatively frequently in sick cats, but does not usually cause marked clinical signs. However, if severe hypokalaemia develops this can result in profound clinical signs. The main effect of severe hypokalaemia is generalised muscle weakness. Affected cats usually show difficulty in getting up and walking, and may appear almost ‘drunk’ because of their weakness. A common and characteristic sign of the muscle weakness is also an inability to raise the head into a normal position, so that it is constantly hanging down. In these cases, cats may sit up on their haunches to look around – the so-called “Meerkat” position. Hypokalaemia can also have a number of other effects including marked depression and inappetance.

What causes hypokalaemia?

The most common cause of hypokalaemia is chronic kidney failure – particularly common in older cats. Some medications such as diuretics used to treat heart failure may result in hypokalaemia particularly if your cat is not eating well whilst administering these drugs. A variety of other diseases can also cause or contribute to hypokalaemia, such as adrenal gland problems, but these are less common. A hereditary form of hypokalaemia is recognized in Burmese cats and related breeds (Bombays). These cats usually show signs around 6 months of age and can often be adequately managed by supplementing them with oral potassium.

"The most common cause of hypokalaemia is chronic kidney failure – particularly common in older cats. Some medications such as diuretics used to treat heart failure may result in hypokalaemia particularly if your cat is not eating well whilst administering these drugs."

How is hypokalaemia treated?

The hypokalaemia and associated clinical signs may be quickly corrected by potassium supplementation. In severe cases, potassium may be given through an intravenous drip. This rapidly corrects the hypokalaemia, and reverses the muscle weakness. In less severe cases, and for long-term maintenance of blood potassium, dietary supplementation is usually necessary. A variety of oral preparations are available. Potassium gluconate is the most tolerated form, rarely causing gastric upsets such as vomiting. It is available as tablets or liquid. Depending on the cause, it may be necessary to continue supplementing potassium permanently. Intermittent blood tests are usually required to monitor response to treatment.