Can you fast if you have hypoglycemia?

Depends on cause: For people with a post-prandial hypoglycemia (blood glucose drops after eating) that is related to Insulin resistance, there should be little danger in fasting. People who have a tumor that produces Insulin or who take Insulin but do not lower the dose before a fast, the blood sugar could drop too low when fasting.

Please define: Hi. Please define hypoglycemia. If you're not taking diabetes drugs, true pathological hypoglycemia is vanishingly rare. Do you become confused, lose consciousness, have a seizure? If not, there is a popular self-diagnosis of "hypoglycemia" that isn't real. So, unless you have real, pathological hypoglycemia, you're fine fasting for as long as you want. If you have real hypogly, see endocrinologis

Depends: It depends on the cause of hypoglycemia. Unless you actually have low blood sugar during periods of hypoglycemia, it's generally safe to not eat after midnight for a 8 am labs.

Hypoglycemia is rare: Symptoms include nervousness, sweating, hunger, anxiety, blurred vision, fatigue, fast heart rate, etc. -- however unless you have diabetes and are on Insulin or other medication, have renal or liver disease, cancer or prior stomach surgery -- then true hypoglycemia neveer occurs in human beings. If it a very frequently and incorrectly made diagnosis.