<s>[INST] Hi , My father is around 73 years old recently in a medical checkup it was found that his creatinine level is 1.8,Yes he has high blood pressure as per the test and quite few days back he had swollen legs, though he doesn t have any sugar problem, its been a years ago when he felt some burning sensation in legs, just want to know is his condition is critical. [/INST] Hi Akhil, Thanks for using the Chat Doctor. I am happy to ad Chat Doctor. 6-1.2 with a critical value being >4. Creatinine is used in skeletal muscle contraction and is excreted entirely by the kidneys.  There are slight increases in creatinine levels after meals, especially after eating large amounts of meat. Certain medications can increase your creatinine levels as can diabetes, reduced renal blood flow (from CHF or deny </s>