post–lumbar puncture headache

post–lumbar puncture headache /-lum″bar/ [L, post, after, lumbus, loin, punctura; AS, heafod + acan] , a headache that occurs within a few hours after a lumbar puncture and usually lasts 1 or 2 days to several weeks. It may be accompanied by nausea and vomiting and improves when the patient lies down.