Development and stability evaluation of extemporaneously compounded nimodipine oral suspension

Background Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurological emergency often complicated by delayed cerebral ischemia. While nimodipine remains the only approved pharmacological intervention proven to improve clinical outcomes in this population, significant pharmacokinetic variability and administration challenges in dysphagic patients severely compromise its consistent clinical efficacy. Purpose To formulate an extemporaneously compounded nimodipine oral suspension and to systematically evaluate its physicochemical stability and feeding tube compatibility. Methods A compounded nimodipine suspension was prepared in 1:1 ORA-Plus® and ORA-Sweet® vehicles and stored under refrigerated and room temperature conditions for 28 days. Chemical stability was quantified via high-performance liquid chromatography (HPLC). Physical stability was evaluated by measuring pH, particle size, sedimentation volume, zeta potential, and viscosity. Administration feasibility was tested using standard enteral feeding tubes. Results The compounded formulation maintained chemical stability (90%–110% recovery) for 3 weeks refrigerated and 4 weeks at room temperature. Compared to the crude dispersion prepared by crushing tablets in water, the compounded suspension demonstrated a more negative baseline zeta potential (−21.43 ± 1.89 mV vs. −8.42 ± 2.28 mV, p < 0.001) and higher sedimentation volume (0.99 ± 0.01 vs. 0.26 ± 0.04, p < 0.001), confirming enhanced homogeneity and dispersibility. Rheological analysis confirmed a shear-thinning profile ideal for enteral delivery. Furthermore, feeding tube administration yielded >98% drug recovery without occlusion. Conclusion The compounded nimodipine suspension in this study provides a feasible alternative for enteral nimodipine administration. Future studies are needed to evaluate the formulation’s bioavailability.