Idiopathic intracranial hypertension (IIH), also known as pseudotumor cerebri, is often a debilitating condition characterized by headaches, blurry vision, nausea, and vomiting. Lumbar puncture (LP) is an essential component of the diagnostic and therapeutic approach; however, the procedure itself can cause postlumbar puncture headache. In addition to the clinical presentation, the use of bedside ultrasound to measure the optic nerve sheath diameter may aid in differentiating the 2 conditions.We hereby report a case of a 33-year old woman with known IIH who presented with recurrent headache after the initial therapeutic LP.