What is the ruling on one who cannot fast except by taking medication to avoid severe migraines that lead to nausea, and is it permissible for her to offer fidyah (redemption) by giving charity to the poor for the days she breaks her fast?

If fasting is difficult for a sick person, she is permitted to break her fast, and she is not obligated to use medications in order to be able to fast. If a trustworthy female doctor informs her that her illness is likely to be cured, she must make up the days she missed fasting. However, if her illness is incurable and always causes her severe migraines, then she should break her fast and pay the fidyah (definition) (expiation) for each day she did not fast by feeding a poor person. She must estimate the days she missed fasting since puberty and pay the fidyah for them, because a legally responsible individual is not obligated to fulfill a condition of obligation.