Safety Assessment and Potential Risks of the Glucagon Stimulation Test in the Diagnosis of Secondary Adrenal Insufficiency

Background: Although it takes more time, the Glucagon Stimulation Test (GST) is a reliable measure for assessing growth hormone (GH) and Adrenocorticotropic Hormone (ACTH) secretion. The GST is considered to be a safe test; however, it still has mild side effects and potential risks. Objectives: The objective of this study was to analyze the side effects of the GST while testing adrenal-insufficient patients. Methods: This was a prospective study in which GST was performed in eighty-one patients (44 men, 37 women, mean age: 35.83A9.62 years) with the pituitary disorder. The GST consisted of an intramuscular injection of 1 mg of glucagon. Blood samples were collected at baseline, and 30, 60, 90, 120, 150, 180, and 210 min after glucagon injection for cortisol measurements. All patients were asked to report side effects associated with this test. Results: The mean peak blood glucose level under GST was 9.01A.03 mmol/L, and the mean glycemic nadir was 4.34A.75 mmol/L most frequently found during the 30th minute (p <10-3). During the test, 35 subjects (43.2%) had side effects with a mean age of 42.89 A19.75 years. Frequent side effects included: nausea (29.62%), vomiting (27.16%), abdominal cramps (18.51%) and hunger (13.58%). All patients tolerated the test until the end. Adverse effects were significantly more prevalent in patients older than 50 years (p=0.012). Conclusions: The GST is a reliable alternative to assess the hypothalamic pituitary adrenal axis but should be cautiously used especially in the elderly, despite minor side effects.