Addisonian crisis as a first manifestation of metastatic disease secondary to cancer is uncommon. We report a 63-year-old man with a history of one year of fatigue, weakness, weight loss and repeated symptomatic hypoglycemia. The cortisol stimulation test with ACTH confirmed primary adrenal insufficiency. While receiving adequate treatment with oral hydrocortisone, he presented an adrenal crisis that was treated properly. A CT scan of the lung demonstrated a nodule in the upper right lobe and bilateral adrenal tumors. The biopsy of the lesion revealed a lung adenocarcinoma. The staging with positron emission tomography using 18 fluoroglucose (PET/CT18F- FDG) showed hypermetabolic uptake in the primary lung tumor and in both adrenal glands, suggesting metastatic implants.