Endocrine Abstracts

Introduction: Quetiapine has been found to reduce ACTH and cortisol secretion by blocking serotonergic receptors in clinical trials with healthy subjects and patients with depression, although a clinical presentation has not been reported. We present a patient who presented with acute ACTH deficiency from high dose Quetiapine.

Case report: We report a 21-year-old gentleman treated with high dose quetiapine for acute psychosis. Past medical history was fatigue, brain fog, and headache, following covid 19 infection four years ago. He subsequently had recurrent pulmonary emboli treated with edoxaban but made a full recovery. After being well for one year, he was diagnosed with acute psychosis and treated with 500 mg Quetiapine daily. His fatigue returned with new hypersomnolence, dizziness, and nausea. He had retained erections and pituitary profile showed low cortisol (35 nmol/l at 9AM, 133-537 nmol/l at 6-10AM), with other pituitary hormones like LH and Testosterone in range (LH 6.6 IU/l, 1.7-8.6, Total Testosterone 11.1 nmol/l, 7.6-31.4, SHBG 13 nmol/l, 16-55, calculated free Testosterone 0.336 nmol/l, > 0.225). He had a morning Cosyntropin stimulation test which showed low baseline but moderate adrenal response to Cosyntropin (cortisol 0 min: 16 nmol/l, 30 min: 358 nmol/l, 60 min: 400 nmol/l) and low ACTH (7.5 ng/l, 7.2-63.3) suggesting recent secondary hypoadrenalism. MRI pituitary was normal with preserved high T1 signal from posterior pituitary and unremarkable hypothalamus. Hydrocortisone supplement resulted in significant improvement in his symptoms. Fludrocortisone was added to treat dizziness from probable mineralocorticoid deficiency. His Quetiapine is currently being weaned down.

Conclusion: Our patient presented with acute ACTH deficiency from high dose Quetiapine. It is not certain whether this is reversible following discontinuation of Quetiapine. This demonstrates the need for caution in patients presenting with symptoms of hypoadrenalism following treatment with Quetiapine.