Stability of gabapentin in SyrSpend SF

Gabapentin is used with other medications to control and prevent seizures. It is also used to treat neuropathic pain following surgery due to shingles. Gabapentin comes in many different forms, including capsules, tablets, and oral solutions. Some patients, however, cannot use oral solutions containing alcohol or sorbitol. The objective of this study was to determine the stability of gabapentin in SyrSpend SF, a suspending agent that does not contain either sorbitol or alcohol. The studied samples were compounded into a 50-mg/mL suspension and stored in low actinic bottles at room temperature and refrigerated conditions. Samples were assayed at each time point out to 90 days by a stability-indicating high-performance liquid chromatography method. The method was validated for its specificity through forced-degradation studies. The samples remained within 90% to 110% of the initial concentration throughout the course of the study. Based on data collected, the beyond-use date of this product is at least 90 days when refrigerated or stored at room temperature and protected from light. Based on the final potency data at day 90, the beyond-use date may be longer, but 90 days was the limit of this study.