The first is: New things that invalidate the fast.
Allah (Glory be to Him) explained in His Glorious Book the things that invalidate the fast, Allah (Glory be to Him) says: “It is made lawful for you to have sexual relations with your wives on the night of As-Saum (the fasts). They are Lîbas [i.e. body cover, or screen, or Sakan, (i.e. you enjoy the pleasure of living with her], for you and you are the same for them. Allâh knows that you used to deceive yourselves, so He turned to you (accepted your repentance) and forgave you. So now have sexual relations with them and seek that which Allâh has ordained for you (offspring), and eat and drink until the white thread (light) of dawn appears to you distinct from the black thread (darkness of night), then complete your Saum (fast) till the nightfall. And do not have sexual relations with them (your wives) while you are in I'tikâf (i.e. confining oneself in a mosque for prayers and invocations leaving the worldly activities) in the mosques. These are the limits (set) by Allâh, so approach them not. Thus does Allâh make clear His Ayât (proofs, evidences, lessons, signs, revelations, verses, laws, legal and illegal things, Allâh's set limits, orders, etc.) to mankind that they may become Al-Muttaqûn (the pious).” [Surat Al Baqarah: 187].
When these new things showed up, contemporary scholars exerted efforts to explain the rulings of these new things. We shall mention these matters and their rulings according to the most correct view of scholars.
In the beginning, you have to know that things which invalidate the fast in light of new medical inventions are divided into different types: Some things enter through the mouth, some things enter through the nose, the ear, skin, vagina, urinary tract, and anus, whereas some things invalidate the fast by extracting it from the body.
1- Asthma sprayer:
It is a compressed bottle that contains water, oxygen gas, and remedial materials which are meant to reach the respiratory system, where the largest percentage of which is water, and the rest is made of oxygen and remedial materials.
Scholars have differed whether it invalidates the fast or not, however, the most correct view is: it does not invalidate the fast according to the majority of contemporary scholars. The International Islamic Fiqh Academy in its tenth session that was held in Jeddah, Saudi Arabia, during the period from 23 to 28 Safar 1418 AH reached a decision about asthma sprayer and stated that it does not affect the fast. They explained that by saying that the general rule is the validity of fasting and this certainty cannot be removed according to circumstantial evidence. This substance is transferred to the respiratory system and the arrival of such substance into the stomach is doubtful; thus, the fast is ascertained and cannot be removed by doubt. Assuming that part of this substance reaches the stomach, it will be a small portion which does not affect the fast. They also measured the ruling according to two things:
The first is: Water remains after rinsing, therefore, specialists said: Water that reaches the stomach after rinsing the mouth is more than the substance of this sprayer. Moreover, the Shari`ah ordained rinsing of the mouth during ablution and it did not affect the fast unanimously.
Second, using analogical deduction in comparing between sprayer and the parts that reach the stomach from using Miswak, whereas the Sunnah exhorted to using Miswak during the fast.