Answer
Wa `alaykum as-Salamu wa Rahmatullahi wa Barakatuh.
In the Name of Allah, Most Gracious, Most Merciful.
All praise and thanks are due to Allah, and peace and blessings be upon His Messenger.
In this fatwa:
Throwing up involuntarily does not invalidate your fast in any way. But if you induce vomiting deliberately, then the fast is broken, according to the four schools of jurisprudence, and you ought to make up for the same later.
In responding to your question, Sheikh Ahmad Kutty, a senior lecturer and Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
If you throw up without any voluntary action on your part and against your own will, your fasting is not at all affected. If, on the other hand, you induce vomiting deliberately, then the fast is broken according to the four schools of jurisprudence, and you ought to make up for the same later.
It goes without saying that one must at all times stay away from such activities, for deliberately breaking or causing to break an obligatory fast in Ramadan is a grave sin in Islam.
It has been reported that the Prophet (peace and blessings be upon him) said, “Whoever breaks a single day of fast during Ramadan, without valid reason or sickness, he cannot hope to make up for the same by fasting a whole year (or according to some scholars an entire life-time).” (Abu Dawud)
In other words, the rewards he has deprived himself by invalidating a single day of fast are so incalculable or immeasurable that they cannot be regained by any other means. The above statement of the Prophet (peace and blessings be upon him), however, should never be taken to mean that one must not make up for it. Rather it is absolutely necessary for him to make up for it by fasting later.
Therefore, no adult Muslim, male or female, ought to contemplate breaking a fast in Ramadan without valid reasons or sickness.
In conclusion: throwing up involuntarily (whether due to reasons you have mentioned or others) does not invalidate one’s fast in any way.
Allah Almighty knows best.
Editor’s note: This fatwa is from Ask the Scholar’s archive and was originally published at an earlier date.