C. Aparna*, Vavilala J. Sai Kiriti, M. Bhagavan Raju
Sri Venkateshwara College Of Pharmacy, 86, Hi-tech city road, Madhapur, Hyd 500081, Telangana State, India
*Address of corresponding author
Sri Venkateshwara College Of Pharmacy, 86, Hi-tech city road, Madhapur, Hyd 500081,
Telangana State, India
Background: Carvedilol is a non-selective beta blocker used in treatment of mild to moderate congestive heart failure. The drug has low bioavailability about 25% to 35%. Intestinal lymphatic route is the major uptake mechanism of carvedilol from gastrointestinal tract. Objective: Present work aimed to improve dissolution and bioavailability of drug through SMEDDS, solid dispersions and lipid based solid dispersions for therapeutic uses. Material and Methods: The solubility of carvedilol in various oils, surfactants and co-surfactants was determined, the excipients were screened and those showing maximum solubility were selected for the formulations of Self-microemulsifying Drug Delivery System (SMEDDS). SMEDDS were developed using different combinations of oils, surfactants and co-surfactants. Pseudo ternary phase diagrams were constructed using Triplot V 4.1.2 software and micro emulsification area was determined. Formulations were prepared based on phase diagrams using various proportions of oil, surfactant and co-surfactant. The SMEDDS formulations were selected by evaluating the drug release and self-micro emulsification ability when introduced into an aqueous medium under gentle agitation. Results and conclusion: Among different formulations, formulation containing oleic acid, tween80 and caproyl 90 were selected. The in-vitro drug release of SMEDDS in 0.1N HCl (S-mix ratio 1:3) showed higher drug release (83.98% for 1 hour). Solid dispersions were developed using gelucire 44/14 and gelucire 50/13 as inert carrier. Solid dispersions of carvedilol containing gelucire 50/13 in the drug: carrier ratio of 1:5 was selected as it exhibited higher drug release (85.54% for 1 hour). Lipid based solid dispersions of carvedilol were prepared using SMEDDS and solid dispersions. The drug release from lipid based solid dispersions was found to be higher (92.97% for 1 hour) than SMEDDS and solid dispersions.
Keywords: Carvedilol, SMEDDS, solid dispersions, lipid based solid dispersions