Lokelma Onset of Action
Lokelma (sodium zirconium cyclosilicate) begins lowering serum potassium within 1 hour, with median time to normalization of 2.2 hours, and achieves clinically significant reductions within 48 hours when dosed at 10 g three times daily. 1
Acute Phase: Initial 48 Hours
Within 1 hour: Serum potassium begins to decline, making Lokelma the fastest-acting potassium binder available 2, 3
At 2.2 hours (median): Patients achieve normalization of potassium levels (3.5-5.0 mEq/L) 4
By 24 hours: 84% of patients achieve normokalemia with the standard 10 g three times daily dosing 4
By 48 hours: 98% of patients achieve normokalemia, with mean serum potassium decreasing from 5.6 mEq/L to 4.5 mEq/L 1, 4
At 48 hours: The mean reduction is approximately 1.1 mEq/L with 10 g three times daily dosing 5
Dosing Regimen for Optimal Onset
Initial correction phase: 10 g three times daily with meals for 48 hours is the FDA-approved regimen for rapid potassium lowering 1
Dose-response relationship: Higher doses (5 g and 10 g three times daily) produce significantly greater reductions compared to lower doses (1.25 g and 2.5 g), with the 10 g dose showing the most robust effect 1
Maintenance of Effect
After initial 48 hours: Once normokalemia is achieved, maintenance dosing of 5-15 g once daily effectively sustains normal potassium levels 1
Long-term efficacy: The potassium-lowering effect is maintained for up to 12 months with continued once-daily dosing 1
Clinical Context and Comparison
Fastest available option: Lokelma's 1-hour onset makes it superior to patiromer (which takes approximately 7 hours) when rapid potassium reduction is needed 2
Not approved for acute life-threatening hyperkalemia: Despite its rapid onset, Lokelma is not FDA-approved for emergency treatment of severe hyperkalemia requiring immediate intervention (such as with insulin/glucose or dialysis) 3
Mechanism explains rapid action: Lokelma works throughout the entire gastrointestinal tract (both small and large intestines), binding potassium in exchange for sodium and hydrogen ions, which accounts for its faster onset compared to agents that work only in the colon 6, 7
Important Clinical Caveats
Timing with meals: The FDA label specifies administration with meals during the acute phase to optimize efficacy 1
Patient must consume full dose: Patients must drink the entire reconstituted suspension for the medication to work effectively 1
Monitor for hypokalemia: With 10 g and 15 g doses, hypokalemia occurred in 10-11% of patients, so potassium monitoring is essential after initiation 4
Edema risk: Dose-dependent edema occurs, particularly with maintenance doses ≥10 g daily, due to the sodium content (400 mg per 5 g dose) 8, 4