Grover, V.K., Mathew, P.J., Yaddanapudi, S., & Sehgal, S. (2009). A single dose of preoperative gabapentin for pain reduction and requirement of morphine after total mastectomy and axillary dissection: Randomized placebo-controlled double-blind trial. Journal of Postgraduate Medicine, 55(4), 257–260.

To investigate the effect of a single low dose (600 mg) of preoperative oral gabapentin on morphine consumption after total mastectomy and axillary dissection; to determine if the specified administration of gabapentin is safe 

Before total mastectomy and axillary dissection, patients received 600 mg gabapentin or placebo. Pain, sedation, nausea, vomiting, and side effects were monitored every 30 minutes for 2 hours and then every 2 hours until 12 hours after surgery.

• The sample was composed of 46 patients.
• The age range of patients was 18–75 years. In the placebo group, mean patient age was 44.9 years. In the gabapentin group, mean patient age was 46.6 years. 
• All patients were female. All patients were undergoing total mastectomy with axillary dissection ASA I or II.

• Single setting
• Inpatient
• Postanesthesia care unit

Randomized double-blind placebo-controlled trial

• 100-point pain rating scale
• Observer’s assessment of alertness or sedation
• Reports of nausea and number of episodes of vomiting

• Postoperative morphine consumption was 48% lower in the gabapentin group than in the placebo group (P < 0.001). 
• Compared to patients who received gabapentin, patients who received placebo had significantly higher postoperative pain scores and shorter times to rescue dose (P < 0.001).
• Authors noted no difference between groups in regard to sedation, incidence of nausea, and other side effects.

Pre-emptive administration of a single oral dose of gabapentin, 600 mg, led to a decrease in the use of postoperative analgesic.

• The study had a small sample size, with fewer than 100 patients.
• The study involved only one dose of gabapentin at a single time.
• The study followed patients for only 12 hours after surgery.

The use of preoperative gabapentin was associated with improved pain control and quality of life, without excessive side effects.