Glucose-only Therapy for Potassium Reduction: A Scoping Review

Insulin-dextrose therapy is widely used to manage hyperkalemia but carries a significant risk of iatrogenic hypoglycemia. Glucose alone may reduce serum potassium by stimulating endogenous insulin release, potentially offering an insulin sparing alternative. This scoping review examined studies evaluating the effect of oral or intravenous glucose, without concurrent insulin, on serum or plasma potassium in adults. Nonhuman studies, nonpeer-reviewed sources, and studies where diabetes status could not be determined were excluded. Of 1,105 records screened, 30 met inclusion criteria. Most studies were small and conducted before 2,000, involving healthy individuals and patients with various conditions. A narrative synthesis was performed, with findings categorized by diabetes status and intervention type. Potassium responses varied: in nondiabetic individuals, glucose-only therapy generally lowered potassium, often to a clinically meaningful extent. In contrast, potassium often rose in insulin-dependent individuals. Methodological limitations were common, including small sample sizes, inconsistent statistical reporting, lack of control groups, and limited inclusion of hyperkalemic patients. Although glucose-only therapy may be effective in nondiabetic populations, evidence in people with diabetes is inconsistent and the evidence base is limited. Further rigorous, controlled studies are needed to clarify the role of glucose-only therapy in hyperkalemia management and its impact on hypoglycemia risk. Plain-language Summary Hyperkalemia, a condition where there is too much potassium in the blood, is often treated with insulin and glucose. But insulin can cause low blood sugar (hypoglycemia), which can be harmful. This review examined whether using glucose alone-without insulin-could lower potassium safely. We found that in people without diabetes, glucose-only therapy often lowered potassium. But in people with diabetes, the results were mixed and, in some cases, potassium levels increased. Most studies included in this review were small and had design limitations, highlighting the need for further research.