Fasting: Things That Invalidate a Fast
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1551
Eight things invalidate a fast:
1. Eating and drinking;
2. Sexual intercourse;
3. Masturbation, meaning that a man – either with himself or by means of something – does something other than having sexual intercourse that results in ejaculation. How this applies to a woman was explained in Ruling 345;
4. Based on obligatory precaution, ascribing false things to Allah the Exalted, the Most Noble Messenger (Ṣ), and the successors of the Most Noble Messenger (Ṣ) [i.e. the Infallible Imams (ʿA)];
5. Causing thick dust to reach the throat, based on obligatory precaution;
6. Remaining in a state of ritual impurity (janābah), menstruation (ḥayḍ), or lochia (nifās) until the time of ṣubḥ prayers;
7. Applying liquid enema;
8. Vomiting intentionally.
The laws (aḥkām) relating to these will be explained in the following rulings (masāʾil).