Endovascular procedures have become a mainstay in the treatment of neurovascular pathologies like arteriovenous malformations and aneurysms. Catheter-induced blister-like aneurysms (BBAs) have not been described so far in the neurosurgical literature. The authors report a rare case of a possible, catheter-induced (iatrogenic) BBA of the supra-ventral wall of the internal carotid artery (ICA) post-endovascular coiling for posterior communicating artery (PComA) aneurysm and bring the rapid progression of BBA and the grade prognosis. A 46-year-old female presented with convulsions. Imaging studies showed diffuse subarachnoid haemorrhage (SAH) and a right saccular PComA aneurysm. Endovascular coiling of the aneurysm was performed, and it was uneventful. The patient had a good outcome (modified Rankin Scale of 1) with no neurological deficits and was discharged home on day five. However, on day nine after the first ictus, she experienced a severe headache at home and was rushed to the emergency room where she collapsed. A cranial computed tomography scan showed intracerebral haemorrhage with intraventricular extension and SAH. A cerebral angiogram showed a BBA of the supra-ventral wall of the ICA. A BBA needs to be considered as a complication of an endovascular procedure that may result in rapid neurological deterioration post-coiling due to rupture. The report also illustrates the rapid and catastrophic presentation of BBA.