A young man with no diabetes history developed life-threatening ketoacidosis while combining tirzepatide with intermittent fasting and a low-carb diet — a warning about unsupervised GLP-1 drug use with restrictive diets.
Normal blood sugar, dangerous acid levelsEuglycemic ketoacidosis — blood appears fine by glucose alone, masking a life-threatening metabolic crisis
What the researchers found
A 30-year-old man with no known diabetes developed euglycemic diabetic ketoacidosis (EDKA) — a dangerous acid buildup in the blood without the expected high blood sugar — while taking tirzepatide for weight loss combined with intermittent fasting and a low-carbohydrate diet. The combination of a GLP-1/GIP receptor agonist with ketosis-inducing dietary restrictions created a perfect storm for this rare but serious complication.
Why it matters
As tirzepatide and other GLP-1 drugs become increasingly popular for weight loss, many users are combining them with aggressive dietary strategies like keto diets and intermittent fasting without medical supervision. This case warns that the combination can cause a life-threatening metabolic emergency — one that's especially dangerous because blood sugar stays normal, making it easy to miss.
The numbers in context
1 patient · 30-year-old male · No prior diabetes diagnosis · Tirzepatide + intermittent fasting + low-carb diet
How the study worked
Single case report describing the clinical presentation, diagnosis, and management of euglycemic diabetic ketoacidosis in a patient using tirzepatide alongside dietary interventions for weight loss.
Who was studied
30-year-old man using tirzepatide with intermittent fasting and low-carbohydrate diet for weight loss
What this study cannot tell us
Single case report — cannot establish causation or determine how common this complication is. The relative contribution of tirzepatide versus the dietary restrictions versus possible undiagnosed diabetes is unclear. Case reports represent the lowest level of clinical evidence.
How to read the evidence
Low evidence: single case report representing the lowest level of clinical evidence. Cannot establish how common this complication is or definitively attribute it to the drug-diet combination.
When this study was published
Published in 2026. Extremely timely given the explosive growth in GLP-1 drug use for weight loss and the popularity of combining these drugs with ketogenic and intermittent fasting approaches.
The bigger picture
With millions of people now using GLP-1 drugs for weight loss, often obtained through telehealth or compounding pharmacies with limited follow-up, the risk of dangerous drug-diet interactions is growing. GLP-1 drugs already reduce appetite significantly; combining them with fasting and carbohydrate restriction can push the body into a starvation-like state where it burns fat for fuel and produces dangerous levels of ketone acids. This case adds to a small but growing body of reports warning about EDKA with GLP-1 drugs and underscores why medical supervision matters.
Questions still open
- How common is euglycemic ketoacidosis among people combining GLP-1 drugs with low-carb diets or intermittent fasting?
- Should prescribers specifically warn against ketosis-inducing diets when prescribing tirzepatide or semaglutide?
- Did this patient have undiagnosed latent autoimmune diabetes that predisposed him to ketoacidosis?
Common questions
What is euglycemic diabetic ketoacidosis and why is it dangerous?
Is it safe to do keto or intermittent fasting while on GLP-1 drugs?
Read the original research
A Case of Euglycemic Diabetic Ketoacidosis With Tirzepatide Use and Severe Calorie Restriction.
JCEM case reports, 4(2), luaf324
Citation
Raptis, Dimitrios; Theodoropoulos, Panagiotis; Shah, Mandar Kalpesh; Bloomgarden, Noah; Kishore, Preeti. (2026). A Case of Euglycemic Diabetic Ketoacidosis With Tirzepatide Use and Severe Calorie Restriction.. JCEM case reports, 4(2), luaf324. https://doi.org/10.1210/jcemcr/luaf324