Compatibility and stability studies of levadopa, carbidopa, entacapone and natural bioenhancer mixture

Abstract

Levodopa, Carbidopa and Entacapone are used for the treatment of Parkinsonism disease. Piperine is an alkaloid from Piper
species is reported to enhance the oral bioavailability of co-administered drugs. Piperine can improve the bioavailability of
Levodopa in solid oral dosage forms. The present study was aimed to added Piperine natural bio-enhancer as a formulation
additive in oral formulations of Levodopa, Carbidopa and Entacapone. The physical mixture of Levodopa, Carbidopa,
Entacapone and Piperine in the ratio of 1:1 and the mixture were stored up to four weeks at 40°C/75%RH. In that samples are
analyzed by validated Liquid chromatography techniques. The stability of the mixture was assessed by the use of ICH
guidelines. Statistical experimental designs enable the user to obtain the maximum amount of information, i.e., the
degradation effects of additives (Piperine) and their interactions on the stability of the drug substance. The percentage
impurities of Levodopa, Carbidopa and Entacapone in Piperine after four weeks at 40°C/75%RH and are same like Initial
results. The above studies have proved that Piperine can be used as a formulation additive in oral formulations of Levodopa,
Carbidopa and Entacapone.