I. Eating and Drinking
1582. If a person eats or drinks something intentionally, his fast becomes void, irrespective of whether the thing which he ate or drank was usually eaten or drunk, like bread or water, or not, like mud or the juice of a tree, and whether its quantity is more or less. Even if he takes the toothbrush (Miswak) out of his mouth and then puts it back into his mouth, swallowing its liquid, his fast will be void. Unless the moisture in the toothbrush mixes up with the saliva in such a way that it may no longer be called an external liquid but if he finds out that, it’s in his mouth, as per obligatory precaution he should not swallow it.
1583. If while having food, a person realizes that it is Fajr, he should take the food out of his mouth, and if he swallows it intentionally, his fast is void, and according to the rules, which will be mentioned later, it also becomes obligatory on him to give Kaffarah.
1584. If a person who is fasting eats or drinks something forgetfully, his fast does not become invalid.
1585. As per recommended precaution, a person who is fasting should not use injections and there is no difference between different types of injections, if it becomes necessary to use it and then he used it, his fast will not be void.
1586. If a person observing fast intentionally swallows something which remained in between his teeth, his fast will become void.
1587. If a person wishes to observe a fast, it is not necessary for him to clean his mouth before the Adhan of Fajr prayers. However, if he knows that some particles of food, which have remained in between his teeth, will go down into his stomach during the daytime and then he does not clean it, his fast will become void, whether or not it goes into his stomach.
1588. Swallowing saliva does not invalidate a fast, even if it is collected inside the mouth due to the imagination of sourness or the likes of it.
1589. There is no harm in swallowing one's phlegm or mucous from head or chest as long as it does not come up to one's mouth. However, if it reaches one's mouth, as per obligatory precaution one should not swallow it.
1590. If a person, observing fast becomes thirsty to such an extent that he fears his death out of thirst, it is obligatory for him to drink as much water as to ensure that the fear is averted. However, his fast becomes invalid, and if it is the month of Ramadhan, he should refrain from all acts which would invalidate the fast for the rest of the day.
1591. Chewing food to feed a child or a bird and tasting food etc. that does not usually go down the throat, even if it happens to reach there inadvertently will not invalidates a fast. However, if a person knows beforehand that it will reach down to the throat, his fast becomes void, even if it does not reach down the throat, he should observe its Qadha and if it reached down the throat it will be obligatory upon him to give Kaffarah as well.
1592. A person cannot abandon fast on an account of weakness. However, if his weakness is to such an extent that fasting becomes entirely unbearable, there is no objection in breaking the fast.