Solubility enhancement of terbinafine hydrochloride by hydrotropic technique

Terbinafine hydrochloride is an antifungal drug belonging to the class of allylamines. The drug exhibits poor aqueous solubility and thus results in decrease in oral bioavailability. In the present study, an attempt was made to enhance the solubility of terbinafine hydrochloride using hydrotropic solubilization technique employing different hydrotropesnamely sodium benzoate and ureain different proportions and their combinations. The different hydrotropes were selected based on the saturation solubility exhibited by the drug. Among them best batches of the drughydrotrope combinations of varying concentrations of 5% w/v, 10% w/v and 15% w/v were further subjected for the in vitro dissolution studies and solid-state characterization studies. The results so obtained were an indicative of solubility enhancement of terbinafine hydrochloride in combination of 10% urea, and combinationhydrotropes of 10% urea and 15% sodium benzoate. Thus, the experimental investigation concluded that there is an 1.53, 3.77 fold increase in dissolution profile for drug with 10% urea and combination of drug with 10% urea and 15% sodium benzoate respectively at the end of 120 minutes