When blood samples are taken for the analysis of plasma potassium, it is important to remember that artifactual elevations can occur after an improper venipuncture technique or as a result of in vitro hemolysis of the sample. The correction of hypokalemia, particularly in the presence of cardiac disease, renal disease or acidosis requires careful attention to acid-base balance and appropriate monitoring of serum electrolytes, the electrocardiogram and the clinical status of the patient. Potassium supplements should be used with caution in diseases associated with heart block since increased serum potassium may increase the degree of block. Patients with ostomies may have an altered intestinal transit time and are better treated with other forms of potassium salt. In some patients, diuretic-induced magnesium deficiency will prevent the restoration of intracellular deficits of potassium, so that hypomagnesemia should be corrected at the same time as hypokalemia.
Pregnancy is associated with gastrointestinal hypomotility.
Solid oral potassium supplements should therefore only be given to pregnant women if such therapy is considered essential. Since oral potassium becomes part of the body's potassium pool, provided the body potassium is not excessive, the contribution of Slow-K can be expected to have little or no effect on the potassium level in human milk. Concomitant treatment with potassium sparing diuretics is contraindicated. Since anticholinergic agents have the potential to reduce gastrointestinal motility, they should be prescribed with caution when given concomitantly with solid oral potassium preparations, particularly in high doses. As renal function, and hence the potential for maintaining potassium balance may decrease with age, serum potassium levels should be monitored regularly and dosage adjusted as appropriate.