© 2013 The Cochrane Collaboration. Background: Post-dural puncture headache (PDPH) is a common complication of lumbar punctures. Several theories have identified the leakage of cerebrospinal fluid (CSF) through the hole in the dura as a cause of this side effect. Therefore, it is necessary to take preventive measures to avoid this complication. Prolonged bed rest has been used as a therapeutic measure once PDPH has started, but it is unknown if it can be also be used to prevent it. Similarly, the value of administering fluids additional to those of normal dietary intake to restore the loss of CSF produced by the puncture is unknown. Objectives: To assess whether prolonged bed rest combined with different body and head positions, as well as administration of supplementary fluids after lumbar puncture, prevent the onset of PDPH in people undergoing lumbar puncture for diagnostic or therapeutic purposes. Search methods: We searched the Cochrane Controlled Trials Register, MEDLINE, EMBASE, and LILACS up to June 2013. Selection criteria: We identified randomized controlled trials (RCTs) that compared the effects of bed rest versus early/immediate mobilization, head-down tilt versus horizontal position, prone versus supine positions during bed rest, and administration of supplementary fluids versus no/less supplementation, as prevention measures for PDPH in people who have undergone lumbar puncture. Data collection and analysis: Two review authors independently assessed the studies for eligibility through the web-based software EROS (Early Review Organizing Software). Two different review authors independently assessed risk of bias using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We solved any disagreements by consensus. We extracted data on cases of PDPH, severe PDPH, and any headache after lumbar puncture and performed intention-to-treat analyses and sensitivity analyses by risk of bias. Main results: We included 23 trials (2477 participants) in this review. There was no beneficial effect associated with bed rest compared with immediate mobilization on the incidence of PDPH (risk for bed rest 26.4%; risk for mobilization 20.5%; risk ratio (RR) 1.30; 95% confidence interval (CI) 1.09 to 1.55), severe PDPH (risk for bed rest 10.6%; risk for mobilization 10.7%; RR 1.00; 95% CI 0.75 to 1.32), and presence of any headache after lumbar puncture (risk for bed rest 33.6%; risk for mobilization 28.6%; RR 1.18; 95% CI 1.05 to 1.32). Analyses restricted to the most methodologically rigorous trials gave similar results. Likewise, the two trials that assessed fluid supplementation did not find this preventive measure to be useful in the prevention of PDPH. Authors' conclusions: There is no evidence from RCTs that suggests that routine bed rest after dural puncture is beneficial for the prevention of PDPH onset. The role of fluid supplementation in the prevention of PDPH remains unclear.