What is the sickness which permits a fasting person to break his fast?

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He is sick and has to take medicine during the day
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Fasting makes her lazy and causes her to lose weight; can she not fast?
A surgeon loses concentration because of fasting; is it permissible for him to break the fast?
The doctor took a sperm sample from him; does he have to do ghusl?
He is sick and has to take medicine during the day
Correct Hijaab

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