Good thinking. They are really interesting drugs but as a chemist you may be able to postulate better theories on why based on the structure of the compounds! I'll leave that to you haha. Tylenol basically becomes inactivated. As far as the heart stuff, we really are all over the place. Obviously, we are not understanding it well enough or certain drugs are causing heart issues not from the COX-inhibition. Perhaps the 14% increase with Aleve was true effects from COX-inhibition...but Vioxx DOUBLING cardiovascular mortality....now something else has to be going on there haha.