Development and Evaluation of an Orodispersible Tablet Formation for the Delivery of a Hydrophobic Drug.

Abstract

Orodispersible tablet (ODT) is a promising avenue for drug delivery, offering a dosage form that can be disintegrated instantaneously in the mouth and released the drug that dissolves or disperses in the saliva without the addition of water. ODT can effectively boost the dissolution rate and consequently the bioavailability of several hydrophobic drugs. Additionally, ODT is very attractive and suitable for specific patients who are unable to swallow the traditional tablet. The basic approach in the fabrication of oral tablets for hydrophobic drugs relies on the utilization of superdisintegrants which allow prompt disintegration of tablets after swallowing. In the present investigation, escitalopram oxalate was chosen as a model drug, which is a hydrophobic, antidepressant, selective serotonin reuptake inhibitor (SSRI) drug. Nine formulas of escitalopram oxalate ODTs were prepared by varying the concentrations of three different superdisintegrants: sodium starch glycolate, croscarmellose sodium, and crospovidone to improve the dissolution and release of escitalopram oxalate. Each was used in three different concentrations (2.5%, 5%, and 7.5%), and all the ODTs were prepared by the direct compression method. The micrometric characterization of the powder blend used in the formulations was investigated such as angle of repose, bulk and tapped densities, compressibility percent (Carr's index), and Hausner ratio. Furthermore, the prepared ODTs were characterized in terms of weight variation, thickness, diameter, hardness, friability, in vitro disintegration, wetting time, water absorption ratio, drug content, in vitro dissolution, and accelerated stability study. The results showed that the formula (ODT9) that contained 7.5% of the superdisintegrant sodium starch glycolate had superior characteristics in almost all the tests, with a dissolution rate of 100% after 6 minutes. Also, it was stable under the accelerated stability conditions.