The worst taste experience I ever had was when I accidentally bit down on an ibuprofen gel cap before swallowing it with a small mouthful of room temperature coffee (it was all I had at my office desk). Wow... it instantly numbed the back of my mouth and throat and tasted like volatile chemical waste. I washed it all down as fast as I could with more coffee but that taste and tingly sensation stuck around for 20 minutes.
The ibuprofen did its job though.