Riyad us Saliheen: Hadith 1451

A man came to the Prophet (ﷺ) and said, "What a trouble I suffered from a scorpion which stung me last night!" He (ﷺ) said, "Had you said in the evening: 'A'udhu bikalimatillahit-tammati min sharri ma khalaqa (I seek the protection of Allah's Perfect Words from the evil of whatever He has created),' it would not have harmed you."

[Muslim].