Should macrogol (Polyethylene Glycol) be avoided in patients with Acute Kidney Injury (AKI) stage 1?

Macrogol (Polyethylene Glycol) in AKI Stage 1

Macrogol can be used safely in patients with AKI stage 1, as there are no specific guidelines recommending its avoidance in early-stage kidney injury. 1

Rationale for Safety in AKI Stage 1

Macrogol (Polyethylene Glycol) is not specifically listed as a medication requiring dose adjustment or avoidance in patients with acute kidney injury in major nephrology guidelines. The KDOQI and KDIGO guidelines, which provide comprehensive recommendations for medication management in kidney disease, do not include macrogol among medications that require special consideration in AKI 1.

When reviewing the cautionary notes for prescribing in people with kidney disease from the KDOQI guidelines, macrogol is notably absent from the extensive list of medications requiring dose adjustment or avoidance 1.

Risk Assessment

While there are isolated case reports of nephrotoxicity associated with certain formulations of polyethylene glycol (particularly low molecular weight PEG 200) 2, standard macrogol preparations used for constipation (typically PEG 3350) have different properties:

• Macrogol 3350 is minimally absorbed from the gastrointestinal tract
• It works primarily through an osmotic effect in the bowel
• It does not undergo significant renal elimination

The Acute Disease Quality Initiative (ADQI) provides guidance on when to avoid or discontinue nephrotoxins 1:

• When a drug is considered the potential cause of AKI
• When a suitable and less nephrotoxic alternative is available
• When the drug is considered non-essential

Macrogol does not typically meet these criteria for avoidance in AKI stage 1.

Medication Management in AKI

The management of medications in AKI should be guided by:

1. Assessment of the specific cause of AKI
2. Trends in kidney function over time
3. Volume status assessment
4. Concomitant acid-base and electrolyte disturbances 1

For AKI stage 1, which represents a relatively mild kidney injury (defined as a serum creatinine increase of 0.3 mg/dL within 48 hours or a 50% increase within 7 days), medication adjustments should be targeted to drugs with known nephrotoxicity or those primarily eliminated by the kidneys 1, 3.

Special Considerations

There are some situations where caution with macrogol might be warranted:

• Patients with severe volume depletion (macrogol can draw fluid into the bowel)
• Patients with electrolyte disturbances (particularly at risk with higher doses)
• Patients taking multiple other nephrotoxic medications 4

Alternative Approaches

If there are concerns about using macrogol in a patient with AKI stage 1:

• Consider addressing underlying causes of constipation (immobility, medications)
• Ensure adequate hydration status
• Consider non-pharmacological approaches to constipation management
• Monitor kidney function regularly if macrogol is used

Conclusion

Based on available guidelines and evidence, macrogol can be safely used in patients with AKI stage 1, with appropriate monitoring of kidney function and volume status. Unlike medications specifically identified as nephrotoxic (such as NSAIDs, aminoglycosides, and certain contrast agents), macrogol is not recognized as a medication requiring avoidance or dose adjustment in early AKI 1.