Can theophylline (prescribed for asthma) show up in pre employment drug test as an opiate or illegal substance?

Theophylline: I thought you were given theophylline as a child. In your previous question you said this was not prescribed for over ten years, . What is the real story? Are you trying to find a substitute cause for testing positive on a drug screen? Theophylline will not cause a positive for illegal substances.

No it cannot: Alwaystestclean.Com/false_positive_drug_test_list.Htm the most complete list of cross reactants that cause a false positive drug test on the internet.