what is the creatinine
Creatinine (/kriËÃ¦táµ»náµ»n/ or /kriËÃ¦táµ»niËn/; from Greek: ÎºÏÎ­Î±Ï, translit. kreas, lit. 'flesh') is a breakdown product of creatine phosphate in muscle, and is usually produced at a fairly constant rate by the body (depending on muscle mass).