Vol. 8, Issue 6 (2019)

Author(s):
Swapna R, Dr. Basava Raju D and Dr. Shailaja P

Abstract:
Floating tablets of cephalexin were prepared using Albizia gum, Dammar gum and Moi gum as polymers for controlling the drug release. Cephalexin is a semisynthetic antibiotic derived from cephalosporin C and is almost completely absorbed from the gastrointestinal tract with a bioavailability of 95%. Cephalexin has a half-life of around 1.1 hour. To maintain the therapeutic range, the drug should be administered three to four times a day. Addressing this problem, we attempted to formulate floating tablets of cephalexin, which can provide a constant effective drug level for 12 hours, based on calculations considering pharmacokinetic parameters. Two types of diluents were used and the drug release was compared. Pure drug and optimized formulation were subjected to the drug excipient compatibility studies using FTIR and DSC. The studies revealed that there was no interaction between the drug and excipients. In order increase the drug release channeling agents were introduced namely Lactose and DCP. Precompression parameters were performed to all the formulations and were found to be in the acceptable limit which ensures the good flow properties. Formulation F4CPDL containing gum dammar and lactose as channeling agent showed good results when compared to other formulations. The floating lag time of the optimized formulation was very short and the percentage of drug release at the end of 12hours was found to be high. The drug release kinetics revealed that formulation F4CPDL follows Zero order. In vivo studies were conducted on rabbit and pharmacokinetic parameters of the optimized formulation were evaluated using HPLC method. It was found that floating tablets showed increased t1/2 and decreased Kel. The design signified that the drug release rate from tablets was influenced by the small proportion of polymer mixture and it controlled medicament release upto 12 hrs effectively.