Nanoemulsion formulation containing carbamazepine and levetiracetam: Development and in vitro characterization

Background and Aims: Epilepsy is one of the most disabling and most common neurological disorders, affecting approximately 65 million people of all age groups worldwide. When there is no response to monotherapy in the treatment of epilepsy, the combined use of Carbamazepine (CARBA) and Levetiracetam (LEV), which have different mechanisms of action, can be additive/synergistic and may be useful in the clinic. The aim of our study is to develop a fixed-dose combination (FDC)-nanoemulsion (NE) formulation containing CARBA and LEV for the treatment of epilepsy.Methods: Blank NE (BLNK-NE) and CARBA+LEV-FDC-NE formulations were prepared and carried out the in vitro characterization studies [morphological analysis, centrifugation test, droplet size (DS), polydispersity index (PDI), zeta potential (ZP), viscosity and pH measurements, FT-IR analysis, the percent entrapment efficiency (EE%), and in vitro release study]. Results: The DS, PDI, pH, and ZP values for the BLNK-NE formulation were found to be 117.63 & PLUSMN;3.82 nm, 0.240 & PLUSMN;0.014, 4.62 & PLUSMN;0.03, and (-)26.07 & PLUSMN;3.04 mV, respectively. For the CARBA+LEV-FDC-NE formulation, the DS, PDI, pH, and ZP values were determined as 137.56 & PLUSMN;3.11 nm, 0.225 & PLUSMN;0.013, 4.60 & PLUSMN;0.06, and (-)21.62 & PLUSMN;0.29 mV, respectively. The EE% values obtained for CARBA+LEV-FDC-NE were 97.33 & PLUSMN;0.56% (for CARBA) and 96.73 & PLUSMN;0.91% (for LEV).Conclusion: The CARBA+LEV-FDC-NE formulation was successfully prepared. This formulation had suitable in vitro characterization results.