drug screens

[skylarkn]

I am trying to find out how metabolism can affect a drug screen? I received a perscription for butalbital, took the medication for a day or two. I found out from my work that I can not take that medication. I passed a drug screen 1 day after taking meds, however failed test 1 week later for the butalbital. How is this possible?

[Robert_325]

I am trying to find out how metabolism can affect a drug screen? I received a perscription for butalbital, took the medication for a day or two. I found out from my work that I can not take that medication. I passed a drug screen 1 day after taking meds, however failed test 1 week later for the butalbital. How is this possible?

That makes no sense whatsoever. I can only imagine that the first test was either faulty or was checked improperly. I can't provide any other answer than that. Obviously there is no delayed reaction to any drug. Metabolism can affect results but not in the manner you describe. God bless.