Refraining from Doing Anything that Invalidates the Fast

Imam Khamenei

The following nine deed invalidate a fast:

1. Eating or
2. Sexual
3. An act that causes semen to come out (i.e., masturbation);
4. Failing to take a ritual bath (ghusl) for menses, post-coitus ritual impurity (janābah), or post-childbirth bleeding (nifās) until the dawn (fajr) ritual call to prayer (athān).
5. Enema.
6. Vomiting.
7. Ascribing a lie to Allah, the Prophet or an infallible imam (by way of obligatory precaution);
8. Letting an amount of thick dust reach the throat (by way of obligatory precaution);
9. Submerging the whole head in water (by way of obligatory precaution).

Eating and drinking

Ruling 01. If a fasting person intentionally and knowingly eats or drinks something, whether typical food or drink or non-food items, like paper or cloth, and whether large or small, like drops of water or bits of bread, their fast becomes invalidated.

Ruling 02. If a fasting person inadvertently eats or drinks something, their fast, whether obligatory or recommended (mustaḥab), is not invalidated.

Ruling 03. If a fasting person deliberately swallows food that is stuck on their teeth, their fast is invalidated. However, if one does not know that the food is stuck on their teeth, or if one does not swallow it deliberately and attentively, then their fast is not invalidated.

Ruling 04. Swallowing one’s saliva does not invalidate the fast.

Ruling 05. It is obligatory for one who is fasting to refrain from using nutrient injections, intravenous injections, and volume expanders. However, one is allowed to get non-nutrient injections into the muscle, such as an antibiotic, painkiller or anaesthesia as well as medicine that is placed on wounds and injuries.

Ruling 06. One is allowed to take pills and the like if it is necessary for treating a disease, but the fast is invalidated and one must make up for it.

Ruling 07. Mouth bleeding does not invalidate the fast; however, one should not let the blood reach the throat.

Ruling 08. Chewing food for a child, tasting food and the like, which usually does not reach the throat, does not invalidate the fast, even if it accidentally and unintentionally reaches the throat and is swallowed. However, if one knows from the beginning that it will reach the throat, the fast is invalidated if it is swallowed.

Ruling 09. A person cannot break their fast due to physical weakness, but if the weakness is so severe that one cannot bear it, they may break the fast and make up for it later.

Ayatollah Sistani

Ruling 01. If a fasting person inadvertently does something that invalidates a fast, and with the belief that his fast has become invalid he intentionally does one of those things again, then the rule in the previous ruling will apply to him.
Ruling 02. If something is forced down a fasting person’s throat, his fast does not become invalid. However, if he is forced to break his fast by eating, drinking, or having sexual intercourse – for example he is told, ‘If you do not eat food, we will inflict some financial or physical harm on you’ – and he eats something to prevent the harm from being inflicted, his fast becomes invalid. Furthermore, based on obligatory precaution, his fast also becomes invalid if he is forced to do any of the other things that invalidate a fast.

Ayatollah Makarem Shirazi

Eating and drinking intentionally renders the fast invalid, whether eating familiar things, like bread and water, or unfamiliar things like the bark of a tree, be it of small quantity or large. Even if a toothbrush is taken out of the mouth and again entered into the mouth and that moisture is swallowed, his fast becomes invalid except if that moisture of the toothbrush is little and goes in with the water of the mouth.

Ruling 01. Obligatory precaution is that the fasting person restrains himself from injections and serums which are used in place of food and medicine. However, injections that are given in the limbs to numb the feelings, there is no objection.