Answered by Ustadh Tabraze Azam
Question: If i wash my siwak with water and clean my mouth during the fast, then I taste the siwak flavor, will the fast break if this flavor gets mixed up with your saliva and you swallow it in. Or do i need to spit every time when i used my siwak?
Answer: Wa alaikum assalam wa rahmatullah,
I pray this message finds you in the best of heath and faith, insha’Allah.
No, swallowing the remaining taste of the siwak will not break your fast. [Shurunbulali, Maraqi al-Falah]
However, it would be best to spit out once after using it.
See also: Applying Medicine to One’s Teeth: Does it Invalidate the Fast?
And Allah alone gives success.
Wassalam
Tabraze Azam