http://www.smartgroups.com/message/readmessage.cfm?gid=1423922 &messageid=5628&startid=5629 Actually, although it sounds contradictory, it does happen. Here's how it occurs: The insulinoma occurs first, liberating high levels of insulin. We combat it with prednisone, which raises the blood glucose in spite of the high insulin levels. After months of high insulin levels, the body gradually downregulates the insulin receptors on the cells, which are being overstimulated. As the cells become non-insulin responsive, the animal develops diabetes. Its a form of insulin-unresponsive diabetes (Type 2), and it is seen not infrequently in ferrets on long-term prednisone for insulinoma control. The blood doesn't alternate between high and low - the pattern you see in these ferret is that it is low for a long time, then all of a sudden it goes into the 250-350 range or higher. Another reason to consider surgical treatment in younger ferrets as soon as the disease is diagnosed. With kindest regards, Bruce Williams, DVM [Posted in FML issue 4228]