Fasting
The Ruling on Using the Miswak While Fasting
Shaykh Muhammad al-Wasabi clarifies that using the miswak does not invalidate the fast, as long as nothing from it is swallowed.
Questioner:
Does using the toothstick [miswāk] break the fast?
Shaykh Muḥammad al-Waṣābī:
No it doesn’t break the fast. There is no problem with using it and pieces of the tooth stick should not be swallowed.