16-year-old male presented with a thunder-clap headache while weightlifting. Computed tomography brain imaging demonstrated diffuse subarachnoid hemorrhage (Hunt Hess 4, modified Fisher 4) and left frontal intraparenchymal hematoma, suggestive of a ruptured ACOM aneurysm. Within an hour of presentation, the aneurysm re-ruptured requiring placement of bifrontal external ventricular drains for acute hydrocephalus and aggressive hyperosmolar therapy. Emergent digital subtraction angiography revealed a dissecting pseudoaneurysm of the left MACC, treated with coil embolization and endovascular sacrifice of the parent vessel. Post securement, his hospital course was complicated by profound polyuria with hypernatremia, low serum osmolality, and urine studies consistent with ADI. Management was challenging due to adipsia and development of bilateral supraclinoid ICA vasospasm as a sequelae of his subarachnoid hemorrhage. Patient required close titration of desmopressin and intravenous fluid management. He was eventually stabilized on high dose enteral desmopressin and discharged to acute rehabilitation.