Albuterol is an effective treatment for hyperkalemia through beta-adrenergic induction of potassium (K+) uptake. Levalbuterol, the R-enantiomer of racemic albuterol, is used for the treatment of asthma and 0.63 mg of levalbuterol has the same therapeutic efficacy as 2.5 mg of albuterol but with a decreased adverse effects profile. We hypothesized that levalbuterol can reduce serum K+ levels similarly to albuterol when used in equipotent doses. In a randomized, double blind, placebo-controlled prospective study, we compared the K+-lowering effects of nebulized saline and equipotent bronchodilatory doses of albuterol (10 mg) and levalbuterol (2.5 mg) in healthy adult volunteers. Nine subjects entered each of the three study groups. Serum K+ was measured at baseline, at 30 min (immediately after treatment), at 60 min, and at 90 min. All adverse effects were recorded. The three groups had similar baseline K+ values. Immediately after nebulization, only levalbuterol showed a significant decrease in potassium level (p = 0.024). At 30 and 60 min after treatment, both albuterol and levalbuterol groups had significantly lower K+ values compared to placebo. No significant difference occurred between the albuterol and levalbuterol groups. Levalbuterol caused fewer reported adverse effects compared to albuterol.