Obviously alcohol in the system affects reaction to certain meds, my question was more if I say 5 drinks, do they prescribe for 5, or do they go "yeah, right" and prescribe for like 10 or more. Just curious how big the swing they account for.Well yeah, I would think someone with a high alcohol level in their blood on a consistent basis could severely react with any of the strong medication they give you when recovering from surgery. So yes, it probably does factor into the equation in a lot of ways. For one, it would likely determine if they need to give you a medication that is less reactive to alcohol. For another, it will probably at least cover them, insurance wise, if you have a severe reaction, they can point to the chart and say "She reported 5 drinks a week, under that information, Medication X is perfectly safe. We can't help it if she lied to us and drinks way more than that, thus why she had a bad reaction to Medication X."
And yes, I'm pretty sure it's been studied that when asked questions about behaviors that are considered morally questionable, people will often lie their asses off, even when it's potentially hazardous to their health. So yeah, I would suspect they assume people are under reporting their drug use, partly out of shame/cultural pressure, and also possibly out of fear of some kind of legal reprisal.