The pt is often instructed to lie in the recumbent position for 30-60 min, although this practice does not appear to reduce the risk (estimated at 10-30%) of post-LP headache, caused by a fall in CSF pressure. The post-LP headache is dramatically positional; it begins when the pt sits or stands upright and is relieved upon reclining. Bedrest, hydration, and oral analgesics are often helpful; IV caffeine (500 mg in 500-mL saline given over 2 h) is sometimes tried. For post-LP headaches lasting more than a few days, consultation with an anesthesiologist should be considered for placement of an epidural blood patch; this usually provides rapid relief.