@Nurse Ratched, while I completely agree with your intentions with this post, I can't say I would use a hypothetical to ask the doctor if they drug test because it happened to your sober sister. If the doctor has an ounce of street smarts, and many of them do, then that type of question could actually be a red flag and cause them to require a drug test. With subjects like drug use, depending on the context, I usually believe silence is the best policy. Like don't ask questions and only answer them when asked.
Since we are not telling anyone how to pass a drug test, I don't think this advice would violate any BLUA rules.