Renal disease: CONTRAINDICATED in pre-existing kidney disease (creatine increases creatinine — confounds renal markers). Water retention: 1-3kg initial water weight gain. Interstitial nephritis (rare — case reports). Drug interactions: nephrotoxic drugs (NSAIDs, aminoglycosides — additive renal stress). Generally extremely safe in healthy individuals. Inform renal function testing.
Most extensively studied performance supplement. Increases phosphocreatine stores for ATP regeneration in high-intensity exercise. Used for strength, power, lean mass, and increasingly for neuroprotection. Excellent long-term safety record.
Phosphorylated by creatine kinase to phosphocreatine (PCr) serving as immediate phosphate buffer to regenerate ATP from ADP during maximal-intensity exercise. Osmotically active increasing intracellular water content stimulating satellite cell activation for muscle hypertrophy.
| Population | Safety rating | Max safe dose |
|---|---|---|
| General | Likely safe | 5000mg/day |
| One of the most studied supplements. Safe long-term. | ||
| Kidney Disease | Possibly unsafe | Consult physician |
| May increase creatinine (not creatine) levels, complicating monitoring. | ||
No peer-reviewed clinical trial data found for this ingredient.
Data by supplement.ge — Public Health Institute of Georgia (PHIG)