concern, with only minor levels of mercury being detectable. Two studies reviewed in 2007 found no impurities. Interactions Creatine taken with medications that can harm the kidney can increase the risk of kidney damage: Nonsteroidal anti-inflammatory drugs (NSAIDs) – some examples are ibuprofen (Motrin, Advil) and naproxen (Aleve) Diuretics (water pills) – an example is furosemide (Lasix) Cimetidine (Tagamet) Probenicid A National Institutes of Health study suggests that caffeine interacts with creatine to increase the rate of progression of Parkinson's Disease. Food and cooking When creatine is mixed with protein and sugar at high temperatures (above 148 ℃), the resulting reaction produces carcinogenic heterocyclic amines (HCAs). Such a reaction happens when grilling or pan-frying meat. Creatine content (as a percentage of crude protein) can be used as an indicator of meat quality. Dietary considerations Creatine-monohydrate is suitable for vegetarians and vegans, as the raw materials used for the production of the supplement have no animal origin. See also Beta-Alanine Creatine methyl ester References External links Creatine bound to proteins in the PDB Amino acids Bodybuilding supplements Dietary supplements Ergogenic aids Guanidines Myostatin inhibitors