Batty

crazy mad insane mentally ill nuts demented deranged loony lunatic maniac nutty touched unbalanced unsound wrong balmy silly foolish daft dotty loco cracked off wacky maniacal bonkers loopy barmy bats bananas cuckoo screwy gaga fruity crackers brainsick disordered distraught moonstruck buggy haywire kooky kookie round-the-bend around-the-bend whacky non compos mentis