Just wondering because my doctor always puts "no alcohol 72 hours" on his patients requisition forms for standard blood tests such as cholesterol, electrolytes, liver function, thyroid, etc. The nurse said that he is the only one that does this, and I was just wondering what his reason may be for this. By the way, I am not going to phone him and ask--I'm only curious not concerned. :)

Any thoughts?

Alcohol alters blood constituents. For example, increases red blood cell size MCV, and could also skew the results of a liver function test by altering the ratio of AST, ALT, GGT and other blood components providing misleading results.

In fact, in another context blood assays are often performed to check for previous drinking.

Ref. Am Fam Physician

Thanks DrBill100--I guess I'm lucky my doctor cares enough to consider this when sending me for tests. I respect that and wonder why more doctors don't do the same.