Every time i eat sugary foods/carbs i get dizzy, foggyheaded instantly after i eat and it lasts for hours. blood sugars are normal. is this an allergy?

Glycemic index: The speed that glucose gets into your system can trigger symptoms and sometimes a rebound hypoglycemia. The glycemic index of different foods refers to that speed. For example, a baked potato enters the system very quickly, but butter on the potato slows absorption of the sugars. Similar with white bread compared to wheat pita bread. Consider looking into foods with a lower glycemic index.

No: There is no such thing as an allergy to glucose.

Consider allergy?: Perhaps there can be some type of allergy you have with certain foods? My suggestion would be to keep a food diary of everything you eat along with how you feel after those meals. See if there is a correlation with certain foods you eat and your symptoms. You may find it could be something else you are eating as well!

No: Sugar per se contains no protein and thus not an allergen. In the early phase of diabetes, many people have delayed secretion of Insulin and this might have contributed to your dizziness when the blood sugar level gets too low. It appears that you may be a good candidate to have a glucose tolerance test or a 2 hr pp sugar assay. Talk to your doctor about this.