Chronomodulated drug delivery system of losartan potassium: Formulation and in vitro evaluation

Abstract

Objective: The purpose of current investigation is to design and evaluate press coated tablets of losartan potassium for chronotherapy of hypertension.

Methods: The core tablets of losartan potassium were formulated by direct compression method using super disintegrants (croscarmellose sodium and crosspovidone). The optimized core tablet is coated with guar gum and ethyl cellulose polymer blend using compression coating technique, which were further evaluated for physical parameters, drug content, swelling studies, drug release, stability studies and FTIR studies.

Results and Discussion: The pre, post compression parameters and drug content results of both tablets were within the specified limits of pharmacopeia. Swelling studies of PCT indicates that addition of ethyl cellulose decreased swelling index due to hydrophobic nature. The optimized press coated tablet (LPCT3) showed negligible drug release (˂ 10%) in 6 h lag time followed by drug release (98.9±1.28%) in 10 h which is suitable for chronotherapy. Stability studies indicates that there is no significant difference in drug release during storage condition. FTIR studies indicates that there is compatibility between drug and excipients.

Conclusion: Press coated tablets with polymer blends of guar gum and ethyl cellulose resulted in drug release after a predetermined lag time which is suitable for chronotherapy of hypertension.