After thoroughly examining the functionality of asthma inhalers, consulting specialized experts and acknowledging the critical need for them among respiratory patients, Egypt's Dar al-Ifta has determined that using asthma inhalers during fasting does not nullify the fast. This is based on the fact that the air inhaled through them is essential for breathing during an asthma attack.

The medicine mixed with that air does not vitiate the fast since it is one of the necessary elements for the respiratory process that allows the asthma patient to return to breathing normally.

Moreover, this mixed air in asthma inhalers falls under the exemptions recognized by jurists, which include inhaling substances like road dust, flour dust, smoke from a fire, pollen grains, and whatever the winds carry.

The common characteristic of these exemptions is that they can neither be avoided when breathing the air nor distinguished from it.

Based on this and in reference to the question, it is permissible for respiratory patients to use asthma inhalers during fasting and their fast remains valid.