Sayyiduna Uthman bin Abi al-As (may Allah be pleased with him) said: I came to the Messenger of Allah (peace and blessings be upon him) while I had a pain, and he (peace and blessings be upon him) said: "Place your right hand on it, then say: 'Bismillah, a'udhu bi-'izzatillahi wa qudratihi min sharri ma ajid' (In the name of Allah, I seek refuge in the might of Allah and His power from the evil of what I feel), (say it) seven times." I did so, and Allah, the Mighty and Majestic, sufficed me (and the pain went away).
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8309