 Follow-up will be performed by investigators that are masked to the randomization. Patients will be interviewed over the telephone, alternatively in person if hospitalised, the first 1 and 7th day after the LP.Subjects that do develop PDPH will be treated in-line with established and standardized protocols at the department of Neurology, Nordland Hospital Trust, Bodø. Given that PDPH has a natural history of spontaneous resolution within 1-12 days, patients suffering from PDPH will be treated conservatively for the duration of the first 7 days after PDPH diagnosis. Conservative therapy, based on symptoms severity and patients responsiveness, consist of the following: bed rest, caffeine, analgesics paracetamol, NSAIDS, antiemetics and i.v. hydration. If the headache is severe and disabling and non-respondent after 7 days of conservative therapy, epidural blood patch will be administered. If a patient diagnosed with PDPH has a change in the pain character, or develops additional neurological manifestations, an urgent brain CT scan or MRI is indicated to exclude rarer potentially life-threatening intracranial complications. 