I am about to go on acutane and need blood work down, i have a week of abstinence from weed. will it come up anything about it? liver blood count.

They won't look: The monitoring for accutane is an effort to be sure you are not one of the few that show a real pattern of liver injury during use. They will not look for weed derived chemicals. In most of the US you must sign a permit to be tested for it or other drugs unless it is part of a work related monitoring plan that you agreed to when you became employed.

Agree with Dr. F: Just for the sake of completeness, weed use is usually tested by examining urine. In a heavy chronic user, weed residue could be detectable as long as 90 days. Do not use tobacco, alcohol, weed or other street drugs. Nutrition: http://www.choosemyplate.gov/.