Formulation and Evaluation of Oro-Dispersible Paediatric Sildenafil Tablets Using Jute Plant Mucilage

Abstract

Sildenafil citrate a phosphodiesterase 5 inhibitor is a vasodilator used in the management of pulmonary arterial hypertension in both adults and children. In the latter, no dose specific formulation is locally available. Paediatric doses are prepared extemporaneously by splitting the adult dosage forms a process which is tedious and error prone. This work aimed to develop a convenient and dose specific oro-dispersible tablet of Sildenafil citrate for paediatric patients. Additionally, use of Corchorus olitorius mucilage as a novel natural superdisintegrant which is non-toxic and a nutritional supplement, would deliver a potentially superior oral dispersible tablet. Mucilage of Corchorus olitorius jute plant was successfully extracted from its leaves and characterized. The high swelling index of 85.7% renders a great potential for its use as a superdisintegrant. For comparison purposes, common synthetic superdisintegrants, namely croscarmellose sodium, crospovidone and sodium starch glycolate were also used for tablet formulation. Twelve batches of tablets each containing 2.5 mg Sildenafil citrate were prepared whilst varying concentrations of each superdisintegrant. Drug excipient compatibility analysis of active pharmaceutical ingredient and all the excipients by infra-red spetroscopy revealed that there were no predictable drug-excipient interactions. The pre-compression studies on powder blends for Carr’s Index and Hausner’s Ratio demonstrated a passable flow character according to the United States Pharmacopoeia 29, hence the tablets were formulated by direct compression. All the batches were evaluated for compendial quality attributes namely weight uniformity, tablet hardness, friability, thickness, wetting time, water absorption ratio, in-vitro dispersion time, assay and content uniformity. Tablet batches formulated with Corchorus olitorius mucilage were similar to the synthetic superdisintegrants batches in most of the attributes, with characteristic mean in-vitro dispersion times of 20.67, 19.33 and 18.67 seconds for the 5 mg, 7.5 mg and 10 mg disintegrant concentrations respectively. Corchorus olitorius mucilage may thus be used as a superdisintegrant in oro-dispersible tablets.