Impaired Absorption of Extended-Release Potassium Chloride in a Patient With a High-Output Ileostomy

Area of Science:

• Gastroenterology
• Pharmacology
• Surgical Patient Management

Background:

• Ileostomy management guidelines recommend immediate-release (IR) medications and avoiding enteric-coated or prokinetic agents.
• Extended-release (ER) potassium chloride is formulated for postpyloric absorption, not colonic, raising questions about its efficacy in ileostomy patients.

Observation:

• A patient with a diverting loop ileostomy received both intravenous and oral potassium chloride supplementation.
• The patient showed poor clinical response to ER oral potassium chloride, requiring high doses (15-40 mEq) for minimal serum potassium increase.
• Upon switching to IR potassium chloride, the patient required significantly less medication (6.67 mEq) for a similar potassium level increase.

Findings:

• Extended-release potassium chloride demonstrated poor efficacy in correcting hypokalemia in an ileostomy patient.
• Immediate-release potassium chloride proved substantially more effective for potassium repletion in this patient.

Implications:

• Patients with ileostomies experiencing inadequate potassium repletion may benefit from early transition from ER to IR potassium chloride formulations.
• This case highlights the importance of considering drug formulation and gastrointestinal anatomy in managing electrolyte imbalances post-surgery.
• Further research into optimal potassium supplementation strategies for patients with altered gastrointestinal tracts is warranted.