Neuraxial blocks continue to be the cornerstone of anesthesia and postoperative analgesia for
normal vaginal delivery and elective caesarean section due to its approved safety and
efficiency for decades. Post-dural puncture headache (PDPH) is still one of the most common
complications of neuraxial anesthetic techniques. The headache could be severe and limit the
activities of the new mother to care for her baby, prolong hospital stay.

PDPH is defined as a headache that develops within five days of dural puncture and can’t be
attributed to any other types of headache and mostly is postural in character.

Neostigmine methylsulfate is a synthetic carbamic acid ester which reversibly inhibits the
enzyme Acetylcholine esterase (AChE) that makes more Acetylcholine molecules available at
cholinergic receptors. Neostigmine is used in anesthesia mainly as a reversal for
non-depolarizing neuromuscular agents.

Intrathecal (IT) neostigmine was tried as an adjuvant to local anesthetics in IT block for
elective cesarean sections to decrease local anesthetic consumption and to prolong
postoperative analgesia. Side effects of IT neostigmine are dose-dependent with doses more
than 25 µg especially nausea and vomiting and could be decreased by increasing the baricities
of the local anesthetic solutions and by early head up position after IT injection. However,
its effect on PDPH was not investigated before in literature.

Parturients will be randomly assigned into one of two groups: the intervention group will
receive 20 µg with IT Bupivacaine and the control group will receive an equivalent volume of
dextrose 5% with the IT Bupivacaine.

The objective of the current study is to evaluate the efficacy and safety of IT neostigmine
as an adjuvant to bupivacaine in reducing the incidence and severity of post-dural puncture
headache in parturients scheduled for an elective cesarean section.