Self-administered tirzepatide linked to starvation ketosis and anorexia nervosa diagnosis in young woman.

Tirzepatide, a dual GIP and GLP-1 receptor agonist, is highly effective for obesity and weight loss due to its potent appetite suppression. The increasing availability of such incretin-based therapies through online services has raised significant concerns regarding potential metabolic and psychiatric complications, particularly in vulnerable individuals. This case highlights a critical gap in medical oversight, where individuals with underlying predispositions to eating disorders may access powerful pharmacological agents without adequate screening or supervision. The risks of starvation ketosis and exacerbation of psychiatric conditions are particularly pertinent in this context.

This case report details a 21-year-old woman with a 2-month history of dieting and binge-purge symptoms who obtained tirzepatide via an online service. She self-administered 2.5 mg weekly for approximately 4 weeks, followed by 5.0 mg weekly for another month, without direct medical supervision. The primary endpoint was the clinical presentation of adverse events. She presented with severe nausea, bilious vomiting, and presyncope, leading to emergency admission. Laboratory evaluation included serum 3-hydroxybutyrate, glucose, HbA1c, and anion gap. Psychiatric evaluation by a board-certified psychiatrist followed discharge.

The patient's body weight decreased significantly from 47 kg to 41 kg, corresponding to a BMI reduction from 17.9 kg/m² to 15.6 kg/m². She developed severe nausea, vomiting, and presyncope, necessitating emergency admission. Tirzepatide had been discontinued shortly before admission due to nausea. > Laboratory evaluation revealed marked ketonemia, with serum 3-hydroxybutyrate levels at 2057 µmol/L, alongside normoglycemia (glucose 79 mg/dL) and a normal HbA1c of 5.1%. She also presented with a mildly elevated anion gap but no clinically significant acidaemia. Following discharge, a psychiatric evaluation confirmed a diagnosis of anorexia nervosa, binge-eating/purging type. At early follow-up, her body weight had increased to 42 kg, and her Eating Attitudes Test-26 (EAT-26) score decreased to 14.