The Conditions under which Dust Invalidates Fast
Issue No. 1360- Allowing thick dust to reach one’s throat, if it is changed in to mud and goes down the throat, makes the fast void, irrespective of whether the dust is of something which is halal to eat, like flour, or of something which is haram to consume. As to inhalers for those suffering from asthma, since the medicine they give off is usually a light and thin gas, it will not render the fast void.
