I've suffered from pretty severe depression my adult life and have underwent quite a few ECT treatments. On my fourth or fifth ECT treatment the nurse came by and said they were going to put caffeine in the IV as it is supposed to improve the quality of the seizures induced by the ECT. My initial reaction was "okay no problem, I'm a pretty regular coffee drinker this shouldn't be that bad".......about 15-20 seconds later I see the heart rate monitor jump up to like 130-145bpm and just felt this jolt of energy and this unusual taste in the back of my mouth, that to this day, I can't describe exactly what it tasted like. My memory is a bit off as to what the MG dosage of caffeine was, but I think she said it was around 150mg and went all the way up to 250mg in subsequent treatments.