Gabapentin: Before Using for Pelvic Pain, Read This

Recommendations to avoid opioids in the treatment of chronic pain have focused our attention on the use of nonopioid medications, including gabapentin. Chronic pelvic pain (CPP) is an unpleasant condition that negatively impacts many aspects of patients’ lives and is challenging for clinicians to treat. (See Chronic Pelvic Pain in Women: Common, Complex and Real.) The Practice Bulletin from the American College of Obstetricians and Gynecologists recommended gabapentin as a pharmacologic strategy for the treatment of CPP.

A recently published high-quality study should cause us to rethink gabapentin’s role in treating CPP. In this British trial, researchers performed a double-blind study at 37 centers which randomized over 300 women age 18-50 years to gabapentin or visually matching placebo for 16 weeks.

To be eligible for this trial, no obvious gynecologic cause of pain could be noted at laparoscopy. Eligible women with CPP had to rate their pain as 4 or higher using a numerical rating scale (NRS), with zero being no pain and 10 the worst pain imaginable.

The gabapentin dose could be increased to a high of 2700 mg daily.

At study conclusion, the primary outcomes — worst and average NRS pain scores — were similar in the gabapentin and placebo groups.

The proportion of women with serious adverse events was 7% in the gabapentin group and 2% in the placebo group, a statistically significant difference. Not surprisingly, side effects known to be associated with gabapentin, which include dizziness, drowsiness, and visual disturbances, were more common in the gabapentin group.

The findings of this trial clearly indicate that because gabapentin is not effective in treating CPP, it should not be used as a first-choice medication to treat this condition.

In my practice, for patients with CPP, I often prescribe the antidepressant venlafaxine off-label and recommend pelvic floor physical therapy.

One last point. Another chronic pain syndrome is vulvodynia. It’s worth noting that a 2018 placebo-controlled trial found that gabapentin did not reduce pain associated with this bothersome condition.