Some drugs used to treat Type 2 diabetes may actually promote spikes in blood sugar, potentially doing more harm than good, a new study suggests.

In research published in the Journal Of Biological Chemistry, British scientists found that a class of drugs known as GLP-1 agonists have the potential to activate the hormone, glucagon, promoting the release of sugars into the blood — a process that the medications are supposed to prevent.
Such drugs include exenatide (Byetta, made by Eli Lilly) and liraglutide (Victoza, manufactured by Novo Nordisk).

Researchers at the University of Cambridge and the University of Warwick stressed that their findings are “speculative at this stage,” and more research needs to be done before "definitive conclusions can be drawn." But they added that the study highlights a “lack of complete information” about the potential impact of the medications, but emphasized there is no evidence that existing GLP-1 agonists are in any way dangerous for patients.

"What we have shown is that we need a more complete understanding of how anti-diabetic drugs interact with receptors in different parts of our bodies," said Graham Ladds, from St John's College, University of Cambridge.

"GLP-1 agonists clearly benefit many patients with Type 2 diabetes and there is no reason to presume that our findings outweigh those benefits. Nevertheless, we clearly lack a full picture of their potential impact. Understanding that picture, and being able to consider all the components of target cells for such treatments, is vital if we want to design drugs that have therapeutic benefits for diabetes patients, without any unwanted side effects."

People with diabetes suffer from excessively high blood sugar levels and resulting complications, because their bodies do not produce enough insulin — the hormone that enables the uptake of sugar from food. According to the World Health Organization, about 347 million people worldwide have diabetes and it is likely to become the seventh leading cause of death in the world by the year 2030.

Among adults, Type 2 diabetes accounts for the vast majority of cases.

GLP-1 agonists are injectable drugs prescribed to patients who have not been able to bring their condition under control through lifestyle changes or with first-stage, tablet treatments.