A passage from the forthcoming book, Inside the Circus, describes Rick Perry’s back pain as bad enough to require “painkillers in sufficient dosages to keep him standing through the two-hour debates,” This is used to partially explain his weak debate performance.

Of course, after the debate, he required sufficient dosages to keep from thinking back on on his two-hour debate performance.

Inside the Circus was written by Mike Allen and Evan Thomas and is expected to be released on Tuesday.