What is hypokalemia?
Hypokalemia is a term that refers to a low blood concentration of potassium. Potassium is an important electrolyte within the body and is vital for the normal function of muscles and nerves. In some situations, the normal control of body potassium concentration is lost, resulting in depletion of potassium and low blood potassium concentrations.
What are the clinical signs associated with hypokalemia?
Mild to moderate hypokalemia does not usually cause significant clinical signs. However, if severe hypokalemia develops, it can cause profound and life-threatening clinical signs. The main effect of severe hypokalemia is generalized muscle weakness. Affected dogs have difficulty in getting up and walking, and may appear almost "drunk" because of their weakness. The inability to raise the head into a normal position, so that the head is held down or the neck is bent, tends to occur much less frequently in dogs when compared to cats. Hypokalemia can also cause marked depression and lack of appetite. Some dogs with hypokalemia may become constipated. In many cases, the dog will have a poor-quality coat.
What causes hypokalemia?
The most common cause of hypokalemia is chronic kidney failure. Severe or chronic vomiting may also cause hypokalemia in dogs.
A variety of other factors can also cause or contribute to hypokalemia (such as diabetes mellitus, diarrhea, diuretic use, IV fluid therapy with low-potassium fluids, malnutrition), but are less common.
How is hypokalemia treated?
Hypokalemia and its associated clinical signs may be quickly corrected by potassium supplementation. In severe cases, potassium may be given intravenously. This rapidly corrects hypokalemia and reverses muscle weakness. Your veterinarian will determine how quickly to correct this deficiency, because if intravenous potassium is given too rapidly, it can cause heart arrhythmias, or abnormal heartbeats. In less severe cases, and for long-term maintenance of blood potassium, dietary supplementation is usually necessary.
The oral supplements, potassium gluconate or potassium citrate, are well tolerated and are available as a palatable supplement to add to the diet. Depending on the cause, it may be necessary to continue supplementing potassium permanently. Intermittent monitoring of response to treatment is usually necessary through analysis of blood samples, to ensure the supplementation is adequate but not excessive. Excessive potassium levels may also cause problems, primarily with the heart.