Entering the toilet
بِسْمِ اللَّهِ، اللَّهُمَّ إِنِّي أَعُوذُ بِكَ مِنَ الْخُبْثِ وَالْخَبَائِثِ
Bismil-lah. Allahumma innee a'oothu bika minal-khubthi walkhaba'ith.
In the name of Allah. O Allah, I seek refuge in You from the male and female devils.
NoteThe opening "in the name of Allah" is an addition narrated by Sa'id ibn Mansur.