Sayyidah Asma' bint Umays (may Allah be pleased with her) said: The Messenger of Allah (peace and blessings be upon him) taught me some words to say at times of distress: "There is none worthy of worship except Allah; He is my Lord; I do not associate anything with Him."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20734