Hypoglycemia following hyperglycemia

Has anyone had an episode of hypoglycemia following hyperglycemia? Today I went in for my follow-up glucose tolerance test after failing the test about 6 weeks ago. I checked my bg with my glucose meter right before my 2-hour blood draw and it was 255. Similar to the 2-hour value obtained the last time. I then went grocery shopping to walk off the glucose and I was on my way home when I started to feel dizzy, clammy and the feeling I get before I pass out. I stopped the car and measured my glucose and it was 59.

I’m currently not on insulin or any drug for that matter. Has this happened to anyone?

There’s a name for what you describe and it happened to me a few times before I was diagnosed with T1D. It’s called reactive hypoglycemia. Google it; it’s a real thing.

As I understand it, a failing glucose metabolism is unable to keep up with the insulin demands of a meal. The initial insulin burst in response to a meal is called a phase 1 insulin release. Since the phase 1 release isn’t sufficient and the rising glucose level signals for the pancreas to release too much of the phase 2 response. Phase 2 is normally a slower release of less insulin compared to the phase 1 action. Phase 2 basically cleans up what the phase 1 insulin misses.

So the phase 2 release over-reacts and releases too much insulin and drives the glucose level hypo. This often occurs 2-3 hours after eating. At least that’s what I experienced.


Thank you Terry! You’re right, reactive hypo is what happened. Mine happened at around 3.5 hours after chugging the glucose drink. Well, looking up, it doesn’t seem that serious and I guess not drinking sugary drinks on an empty stomach is one of the things you can do to prevent from happening again. Hopefully no more glucose tolerance tests to send me to hypo state again!

My reactive hypoglycemia came following a bowl of breakfast cereal in the morning. Cereal, milk, and fruit absorbs almost as quickly as a sugary drink.

I had the same thing happen after a 3 hour GTT. From another group I’m in it seems like it’s not that uncommon.

Yikes. Cereal does that too? I rarely have cereal for breakfast but it’s good to keep that in mind. I LOVE sweet pastries (I don’t eat them anymore) and wonder if they causereactive hypoglycemia too.