Ali ibn al-Hasan ibn Faddal narrated from Ali ibn Asbat, from Ala al-Qalla, from Muhammad ibn Muslim, from Abu Abdillah عليه السلام, peace be upon him: Imam عليه السلام said: “The fasting person may use the tooth-stick (siwak) at whichever part of the day he wishes, but he should not use a moist stick. He may soak himself in water, pour it (water) over his head, cool himself with a cloth, sprinkle the fan (al-mirwahah), and sprinkle the reed mat (al-buriya) beneath him, but he should not immerse his head in water.”