Acarbose is a medication for diabetes, taken to lower blood sugar. It works by blocking an enzyme (alpha glucosidase) that breaks down sugars, leading to less sugar being absorbed, and consequently decreased blood sugar spikes after eating.
So when a patient told me she was taking it to prevent hypoglycemia, I thought she might be confused. Then she mentioned she had had gastric bypass surgery, and I know that can cause a lot of changes in how the gut works, so I wanted to know more about this.
Here is what I found:
After-meal hypoglycemia is a potentially severe complication of the Roux-en-Y gastric bypass procedure. A side effect of the surgery called dumping syndrome occurs when rapid emptying of food into the small intestine triggers the release of gastrointestinal hormones.
Some of these patients experience an exaggerated response as carbohydrate-rich food passes into the jejunum, stimulating the release of GLP-1 which causes excess insulin release, leading to hypoglycemia. Reducing carbohydrates in the diet may help mitigate this effect and should be considered before initiating drug therapy. If dietary modifications are not effective, taking acarbose before a meal can prevent carbohydrates from being broken down and thus also prevent the excess insulin and hypoglycemia.
Miglitol is another alpha-glucosidase inhibitor that may be used for this purpose also.