Which medicine to take or food to eat to reduce serum creatinine?

Food and creatinine: You need to see a nephrologist to determine your renal function. This could be done with a 24 hour urine collection for creatinine clearance and protein as well as having some blood sent off for analysis. You will also need a renal ultrasound to see the size of your kidneys. Depending on the result, you may or may not have to change your diet. See a nephrologist for the answer that best suits you.

How high is it?: I'm lean and quite muscular and during my best days lifting weights, my creatinine rose to 1.6 just from being heavily muscled. This is about as high as a healthy man who's not on steroids will get it. Now it's 1.4 which is normal for a fitness guy. The "normal range" is determined for men who do not strength-train. I wrote this considering that you might be in the same situation. Best to you.