Is Lokelma (sodium zirconium cyclosilicate) contraindicated in gastrointestinal (GI) bleeding?

Lokelma (Sodium Zirconium Cyclosilicate) in GI Bleeding

Lokelma is not contraindicated in gastrointestinal bleeding, as there is no evidence indicating it increases bleeding risk or worsens GI bleeding outcomes.

Mechanism and Safety Profile

Sodium zirconium cyclosilicate (SZC) is a non-absorbed, non-polymer compound that works by exchanging hydrogen and sodium for potassium and ammonium ions in the gastrointestinal tract, thereby increasing fecal potassium excretion and lowering serum potassium levels 1. Unlike some medications that can increase bleeding risk, Lokelma:

• Does not affect platelet function
• Is not systemically absorbed
• Works locally in the GI tract
• Has a safety profile generally similar to placebo in clinical trials 1

Evidence on GI Bleeding Risk

A recent national study examining serious adverse gastrointestinal events with potassium binders found:

• The risk of intestinal ischemia/thrombosis or other serious adverse GI events was low with sodium zirconium cyclosilicate
• No statistical difference in intestinal ischemia/thrombosis between SZC and other potassium binders 2
• The composite GI adverse events rate was only 2.4% with SZC, which was not significantly different from patients not receiving any potassium binder 2

Clinical Considerations in GI Bleeding

When managing patients with GI bleeding who also have hyperkalemia requiring treatment:

Medications to Avoid or Use with Caution in GI Bleeding

Several medications are known to increase GI bleeding risk and should be avoided or used with caution:

• NSAIDs like diclofenac and ibuprofen
• Antiplatelet agents (aspirin, clopidogrel, prasugrel)
• Anticoagulants (warfarin, DOACs, heparin) 3
• Combination antiplatelet therapy or combined antiplatelet and anticoagulant therapy significantly increases bleeding risk 4

Management Priorities in GI Bleeding

For patients with GI bleeding requiring hyperkalemia management:

1. Control the bleeding first:

   • Early endoscopy (within 24 hours) is recommended as first-line management for GI bleeding 5
   • High-dose IV PPI therapy for high-risk stigmata bleeding ulcers 5

2. Manage hyperkalemia safely:

   • Lokelma can be used as it does not appear to increase bleeding risk
   • Monitor electrolytes closely during treatment

Special Considerations

• Radiologic imaging: Be aware that sodium zirconium cyclosilicate appears radiopaque on CT imaging, which could potentially be confused with contrast material 6
• Monitoring: Regular monitoring of serum potassium is necessary to avoid hypokalemia, which occurred at a low incidence in clinical trials 1

Conclusion

While many medications commonly used in cardiovascular disease management (anticoagulants, antiplatelets) are associated with increased GI bleeding risk 4, there is no evidence suggesting Lokelma increases this risk or is contraindicated in patients with GI bleeding. It represents a safe option for managing hyperkalemia in patients with active or recent GI bleeding.