Why Medication Changes Everything About Fasting
Most people who fast do so without a second thought about timing. But if you take insulin, sulphonylureas such as glipizide or glibenclamide, or certain blood pressure drugs, an empty stomach is not neutral. Sulphonylureas lower blood glucose whether or not you have eaten, which means a skipped meal on the same dose can push glucose low enough to cause shakiness, sweating, confusion, or a blackout. Some antihypertensives, particularly diuretics, accelerate fluid loss during a fast and can drop blood pressure to the point where standing up becomes dangerous. The drug has not changed. Your body's response to it has.
