What is the ruling on using an asthma inhaler (such as Ventolin and the like) while fasting, does it invalidate the fast, and what is required of someone who used it not knowing the ruling?

Scholars have differed concerning the ruling on using an asthma inhaler for a fasting person. Some consider it to invalidate the fast because its dissolved particles reach the stomach cavity, while others do not consider it so, as it is merely gases to expand the bronchial tubes.

If the inhaler invalidates the fast, and asthma is a chronic disease for which the inhaler cannot be dispensed with during fasting, then there is no harm in using it. In such a case, the patient must feed a poor person for each day they break their fast.