Why is the asthma inhaler used by asthmatics not considered to break the fast?

Most contemporary scholars hold that using an asthma inhaler does not invalidate the fast, and this is the correct view. They cite several proofs for this:

1. The default is the validity of the fast, and the possibility of a portion of the spray reaching the stomach is doubtful.

2. If a small amount does reach the stomach, it is excused by analogy with rinsing the mouth (madmadah) and using the tooth-stick (siwak), where a portion of the water or siwak particles remains in the mouth and goes down to the stomach without invalidating the fast.