A post-dural puncture headache (PDPH) is a type of headache that can occur after a spinal tap or epidural anesthesia. It happens when the protective covering of the spinal cord, called the dura mater, is punctured, leading to a leak of cerebrospinal fluid. This fluid loss can cause a decrease in pressure around the brain, resulting in a headache. Symptoms of PDPH typically include a dull, throbbing pain that worsens when sitting or standing and improves when lying down. Other symptoms may include neck stiffness, nausea, and sensitivity to light. Treatment often involves rest, hydration, and sometimes a blood patch to seal the leak.