This is the most common deficiency seen in our patients after gastric bypass surgery. Conversely, it is the most common deficiency seen in our patients before the operation. Gastric Bypass reroutes the food away from the distal stomach and the first portion of the small intestine – the duodenum. The duodenum is where most elemental iron is picked up in the intestinal tract. Because of this, gastric bypass results in worse iron absorption. We screen all patients for iron deficiency pre-operatively: if they are low, we give supplemental iron and see if iron level rise in the blood to normal levels. If iron remains low then it can be assumed the patient has poor iron absorption. We do not recommend gastric bypass in these patients. For those whose iron levels rise to normal we can still recommend gastric bypass if they choose that surgery.
In patients who develop iron deficiency after operation we will treat the deficiency with a ferrous fumarate formulation (REPLIVA) for 2 months. If they return to normal we would recommend a maintenance iron formulation to be taken from then on. Occasionally, iron deficiency can be profound after gastric bypass surgery necessitating iron infusion therapy intravenously.