What are the things that invalidate the fast?

As the primary element of fasting is to abstain from eating, drinking and sexual intercourse, these and similar acts done while fasting invalidate the fast. Eating and drinking includes all things possible to eat and drink. All smoky and pleasure inducing substances with tobacco origin such as cigarette and hookah, and all substances consumed due to addiction such as narcotic drugs fall into the scope of the things that invalidate fasting (Ibn Abidin, Radd al-Muhtar, III, 386-387). Whatever the reason might be, medication consumed orally is subject to the same judgment as well.

Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS,

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