shithouse crazy 

A state of crazy that is beyond repair. The most severe form of crazy.

Look at Francy. She has gone shithouse crazy!

shithouse crazy by studstud October 22, 2011

crazy as a shithouse rat 

Deranged, demented behavior that others deem similar to that of a rodent that dwells in a wood shithouse.

He's crazy as a shithouse rat! If his toes slip off that steering wheel that car's gonna roll.

crazy as a shithouse rat by Rev Tolby November 1, 2007