I was on Effexor XR Max Dose, and one day when I realized that it had effectively killed all feelings I stopped cold turkey, zero side effects. My doctor thinks I have a very high drug tolerance, to the point that anything I'm put on nowadays is just started at close to the max dose. I'm on a drug right now that is prescribed at a level that would normally result in death for most people, and he thinks I can go higher if I need to.

Downside is pain drugs don't work, at all. He told me they'd need to give me IV pain meds if I really needed any pain suppression.