Other Causes of Reactive Hypoglycemia
By far, the most common type of hypoglycemia is reactive hypoglycemia caused by insulin resistance but there are other causes, all much rarer.
Alimentary hypoglycemia
Alimentary hypoglycemia is caused by food being dumped too quickly from the stomach into the small intestine. This causes the carbohydrate to be released too quickly, and this is followed by an over-reaction of the pancreas, and over production of insulin. Alimentary hypoglycemia occurs with an abnormality of the stomach, usually because of stomach surgery. Unlike the normal stomach, which can hold food over a long period, the reduced size of the stomach after surgery makes the holding time shorter. Alimentary hypoglycemia can also occur in some cases of gastrointestinal abnormalities not caused by surgery, depending on where in the system the problem is.
The sudden drop in blood sugar can be very dangerous and, in rare cases, can cause seizures and coma. Usually symptoms will appear a half hour to two and a half hours after eating.
Alcohol induced hypoglycemia
Alcohol can cause an excessive release of insulin when it is taken with carbohydrate. Mixed drinks (mixers are mostly carbohydrates and sugars) taken alone or with a carbohydrate snack is the worst scenario since the combination of alcohol and carbohydrate causes a sugar spike. The pancreas over-reacts, releasing too much insulin and the blood sugar can drop very low, very quickly.
Fasting Hypoglycemia
Fasting hypoglycemia is the rarest, but most serious form of hypoglycemia in non-diabetics. It is very unlikely that your hypoglycemia is the fasting form, even though it may seem that you have symptoms when you haven't eaten for a while. Fasting hypoglycemia is very specifically defined as the experience of hypoglycemia symptoms occurring more than five hours after you have eaten. Most reactive hypoglycemics experience symptoms only1.5-3 hours after eating.
If you have fasting hypoglycemia, the hypoglycemia symptoms probably won't be the most pressing of your symptoms, and you already know you are sick.
The following sections describe some causes of fasting hypoglycemia. If you are experiencing hypoglycemia symptoms five or more hours after eating, please see your doctor as soon as possible!
Disclaimer: I am not a doctor, so please don't use these articles to diagnose yourself. They are only intended to provide information.