Introduction:
Preemptive analgesia is an antinociceptive treatment that prevents establishment of altered processing of afferent input. Gabapentin, a structural analogue of gamma-amino butyric acid, has been used as an anticonvulsant and antinociceptive drug and is claimed to be more effective in preventing neuropathic component of acute nociceptive pain of surgery.

Material and Methods:
Fifty patients of ASA grade I and II were assigned to receive oral 600mg Gabapentin or Placebo 2 hours before surgery. Surgeries were conducted under spinal anesthesia. Post operatively pain was assessed by visual analogue score (VAS) at 2, 4, 8, 12 and 24 hrs. Patients were given rescue analgesic on demand. Sedation score and total numbers of analgesics during first 24 hours postoperatively were noted.

Results:
Gabapentin group resulted in faster onset of motor and sensory block, significantly longer duration of analgesia, substantial reduction in post-operative pain and the rescue analgesics. Patients remained in sleeping but co- operative state and Gabapentin group were not associated with side effects when compared with placebo group.

Conclusions:
Preemptive use of Gabapentin 600mg orally significantly prolongs the analgesia with reducing postoperative pain and rescue analgesics in patients undergoing total abdominal hysterectomy under spinal anesthesia.