As-Salamu ^Alaykum. Ramadan mubaarak brothers.
Question does swallowing balgham (phlegm from the head or congestion) break fasting?
Bismillah, praise be to Allah the lord of the worlds, and may Allah raise the rank of Prophet Muhammad peace be upon him and his kind Aal and companions,
There are different sayings regarding the phlegm or congestion that drips from the head into the throat.
According to Imam ash-Shafi^iyy: if the phlegm reached to the part of the throat above where the exit of the letter ha’ (ح) is, and the person swallowed it, this would invalidate his fasting. However,
According to Imam Abu Hanifah: even if the phlegm reached to the tongue and the person swallowed it, his fasting is not invalidated, as long as he does not swallow it after separating from his mouth.
As for one to force himself to vomit, either by inserting his finger or other than that into his mouth invalidates the fasting. In the case when the person forces himself to vomit, whether or not he swallows some of his vomit, his fast is invalidated and he has to make it up. However, the one who vomited not because he purposely forced himself to do so does not break his fast as long as he does not swallow any of the vomit or saliva mixed with the najas-filth. But swallowing one's pure and unmixed saliva does not invalidate the fasting.
Integrals of Fasting
The integrals of fasting are two:
1. Each night to make the intention to fast the following day
2. To abstain from sexual intercourse, masturbation, and inserting anything with a volume into the head or the body cavity through an open inlet, excluding one’s pure, tahir saliva while still inside the mouth during the time from the dawn until the sunset.
Note: Masturbation or making the semen come out of one by using the hand or the like invalidates one’s fasting, whether one used his own hand, or the hand of his wife, or because of a kiss, or because of other physical contact. If, however, one experienced a wet dream or semen exited from him because of certain thoughts, one’s fast is not invalidated.
Finally, the Muslim must abstain at all time from committing apostasy (Riddah), i.e. committing any type of blasphemy (Kufur) which takes him out of Islam.
Apostasy kufur invalidates Fasting even if one returns to Islam afterwards. After returning to Islam (By leaving the blasphemy and uttering the two testifcations of faith - Shahadatain) one must abstain from eating and other invalidators of Fasting during the whole day. Moreover, one must make up the invaldated day(s) of Fasting after Ramadan.