Orally disintegrating tablet containing carbamazepine and levetiracetam: formulation and in vitro and in vivo characterization.

This study aimed to prepare and characterize the orally disintegrating tablet (ODT) formulations containing the combination of levetiracetam (LEV) and carbamazepine (CBZ) (CBZ + LEV combination) for the treatment of epilepsy. The ODT formulations were prepared using the lyophilization (L) and direct compression (DC) methods. The flowability of the mixed powders used for DC formulation was evaluated. The quality control tests for the ODTs were performed. Also, the antiepileptic effects of pure drugs, their combination, and the suspension of CBZ + LEV-DC-ODT formulation were evaluated in the rats with pentylenetetrazole (PTZ)-induced epilepsy model. The obtained results for the mixed powders of the DC formulation (angle of repose: 26.18 ± 0.794°; compressibility index: 15.24 ± 0.764%) suggest that the flow properties of the powder blend were suitable for the preparation of CBZ + LEV-ODT using DC method. The mean values of diameter and hardness of L-ODTs and DC-ODTs were found to be 16.87 mm and 16.18 mm and 11.96 N and 30.11 N, respectively. The friability of both formulations was <1%. Both formulations were disintegrated in seconds. Drugs in L-ODT had faster dissolution than those in DC-ODT. Compared to the seizure scores obtained for the groups treated with LEV or CBZ, generally, there was a higher decrease in seizure scores in the groups treated with CBZ + LEV combination or the suspension of CBZ + LEV-DC-ODTs. Consequently, the ODT formulations containing the CBZ + LEV combination might be beneficial in the treatment of epilepsy.

Carbamazepine and levetiracetam-loaded PLGA nanoparticles prepared by nanoprecipitation method: in vitro and in vivo studies.

Objective: The aim of this study was to develop the PLGA nanoparticles (NPs) containing carbamazepine (CBZ) and levetiracetam (LEV) combination (CBZ + LEV) for the treatment of epilepsy and to in vitro characterize the prepared NPs.Significance: LEV and CBZ, which are antiepileptic drugs, are used in the treatment of epilepsy. Nano-sized formulations are prepared to use for different purposes such as to improve the solubility/the physicochemical properties and bioavailability of drugs, to decrease their doses and frequency of administration, and to reduce side effects of drugs.Methods: CBZ + LEV-PLGA-NPs were prepared by a modified nanoprecipitation method and in vitro and in vivo characterized. Also, the antiepileptic effect of the NPs was evaluated in vivo in a rat epilepsy model.Results: The mean particle size and zeta potential of CBZ + LEV-PLGA-NPs were 180.62 ± 6.260 nm and -27.08 ± 3.110 mV, respectively. The values of encapsulation efficiency (EE%) of CBZ and LEV were 51.00 ± 5.944% and 2.05 ± 0.367%, respectively. CBZ showed a biphasic release profile with initial burst release followed by a sustained release. Ninety percent of CBZ was released from NPs within two days; however, % LEV release from NPs reached about 80% within 30 min.Conclusion: Our results showed that a decrease in seizure scores in the group treated with CBZ + LEV was observed and also, CBZ + LEV and CBZ + LEV-PLGA-NPs had similar antiepileptic activity. The NPs containing CBZ + LEV might be beneficial in the treatment of epilepsy.