Depomed's Gabapentin Extended Release is an investigational, extended release formulation of gabapentin that is being studied for the treatment of hot flashes in postmenopausal women.

The primary objective of this clinical trial is to determine the optimal dose of Gabapentin ER in reducing the number and severity of hot flashes in postmenopausal women. Patients will be randomly assigned to Gabapentin ER or placebo, with a 1 in 4 chance of getting placebo. The total study investigational treatment duration after screening and baseline will be 13 weeks. The primary endpoint of the trial is to compare the number and severity of hot flashes during the investigational treatment compared to baseline. Sleep quality will also be evaluated.

Inclusion Criteria:

1. Generally healthy, postmenopausal women who seek treatment for hot flashes.
2. Patients using hormone replacement therapy (HRT) must be willing to discontinue treatment.
3. Patients must be experiencing at least 7 moderate to severe hot flashes per day.
4. Patient must be willing to commit to 3 (optionally 4) overnight stays at the study site that will include frequent blood sampling.

Other inclusions apply.

Exclusion Criteria:

1. Patients with hypersensitivity to gabapentin.
2. Patients with severe chronic diarrhea, chronic constipation, uncontrolled irritable bowel syndrome (IBS) or unexplained weight loss.
3. Patients treated with estrogen pellets or injectable progestin drug therapy within 6 months.

Other exclusions apply.