What are the contraindications for taking creatine?

Contraindications for Taking Creatine Supplements

Creatine supplements should not be used by individuals with pre-existing kidney disease or those using potentially nephrotoxic medications. 1, 2

Primary Contraindications

• Chronic kidney disease (CKD), especially with glomerular filtration rate (GFR) <30 mL/min/1.73 m² 1, 2
• Concurrent use of nephrotoxic medications 1
• Pre-existing conditions that increase risk for renal dysfunction, including:
  • Diabetes 2
  • Hypertension 2
  • Reduced glomerular filtration rate 2

Special Considerations

Kidney Function

• While creatine is generally safe for those with normal kidney function, it can affect kidney function measurements 1, 3:
  • Temporarily increases serum creatinine levels
  • May falsely suggest kidney function impairment
  • Can lead to misdiagnosis of chronic renal failure when estimated GFR is calculated based on serum creatinine

High-Risk Populations

• Individuals with a single kidney should exercise caution, though limited evidence suggests short-term use may not significantly affect kidney function in this population 4
• Elderly patients with decreased renal function should avoid creatine supplementation 3
• Athletes using multiple supplements simultaneously should be cautious, as combination use has been associated with liver and renal complications in some cases 5

Dosing Concerns

• High-dose supplementation (>3-5 g/day) should be avoided in individuals with risk factors for kidney dysfunction 2
• Prolonged use at higher than recommended doses may increase risk of adverse effects 5

Monitoring Recommendations

• Pre-supplementation assessment of kidney function may be advisable for those with risk factors 2
• Regular monitoring of kidney function is recommended for individuals who choose to use creatine despite having risk factors 3
• Discontinue use if experiencing adverse effects or if kidney function tests show abnormalities 1, 3

Important Caveats

• When combined with high-protein diets, creatine supplementation may increase blood urea nitrogen, further complicating kidney function assessment 1
• The most common adverse effect is transient water retention in early stages of supplementation, which is generally benign 5
• Current evidence suggests creatine is relatively safe for healthy individuals without pre-existing kidney conditions 1, 2, 3