@SusanEllen66 It isn't resistance. It's 'run-it-through-the-liver-in-jig-time-and-out-the-nether-orifices.' The body metabolizes all drugs, at least most and to an extent, such that they have 'half-lives' where after a certain period half of the blood levels exist from the most potent levels after ingestion. Drugs like Eliquis and other direct-acting-oral anti-coagulants have have lives between 10-14 hours, depending on the patient. Caffeine has a half-live of about 5 hours for most metabolisms/people. In this person's case, the liver quickly renders whatever she/he is taking and renders it innocuous. So, this person spends a lot of time with no desired effect from the drugs.

@SusanEllen66 The meds go through my system fast with something to do with my liver pushing the meds out quicker.

@SusanEllen66 I have to take small amounts more times a day, because my liver kicks the drugs out to fast.