Despite the strong results, there is a reason why experts are very cautious in recommending the use of semaglutide and tirzepatide in patients with type 1 diabetes. These powerful drugs carry very real risks for people with this condition. Drugs must be managed in unique ways, using new strategies that are not yet fully agreed upon by experts.
There are two deadly obstacles that everyone with type 1 diabetes must always avoid. It is a threat of severe hypoglycemia (hypoglycemia) and diabetic ketoacidosis (DKA). GLP-1 drugs are suspected of increasing their respective risks.
GLP-1 and DKA
GLP-1 quickly became notorious for its adverse gastrointestinal side effects. For example, the highest dose of semaglutide causes diarrhea in 32 percent of users and vomiting in 25 percent. For most people, these side effects go away as the body gets used to the drug.
However, the risk increases rapidly for people with type 1 diabetes. This is because dehydration symptoms such as vomiting and diarrhea can quickly lead to DKA, which is ultimately caused by severe insulin deficiency. If a type 1 diabetic is unable to eat or drink due to stomach problems, they will inevitably use less insulin, which only further increases their chances of developing DKA.
People with type 1 diabetes should be especially careful when using GLP-1 drugs because they have DKA. This condition can be fatal without emergency treatment.
GLP-1 and hypoglycemia
On the other hand, GLP-1 fundamentally influences insulin requirements and may therefore increase the risk of severe hypoglycemia. Most diabetics who receive injections of GLP-1 drugs experience increased insulin sensitivity.
GLP-1 itself works in a glucose-dependent manner, so it doesn’t often cause hypoglycemia, but if people with type 1 diabetes don’t adjust their insulin usage quickly, they run the risk of overusing it and causing blood sugar levels to drop dangerously.
At the Barbara Davis Diabetes Center, Garg teaches patients to reduce their insulin by 20% when they first start GLP-1. He and his colleagues continued to suggest decreasing insulin doses as participants stepped up to higher GLP-1 doses.
No one in this study was hospitalized with severe hypoglycemia or hyperglycemia. But Garg has had horrifying experiences in which his patients “were afraid of hypoglycemia, so they took too much insulin and started taking even less insulin than advised, which put them at high risk of DKA.”
Garg took the potential danger seriously, saying, “We monitored these patients closely.” All participants wore continuous blood sugar monitors, allowing doctors to remotely monitor blood sugar levels. In the real world, clinicians cannot easily provide that level of guidance.
Garg is “absolutely” concerned about the use of GLP-1 in settings that are not very carefully controlled. “I’m certainly concerned that these drugs are being used ubiquitously in patients with type 1 diabetes,” he says.