Comparative evaluation of Irvingia gabonensis seed fat extract and other bases in promethazine hydrochloride suppository formulations

Abstract

A study has been made on the formulation and evaluation of promethazine hydrochloride suppositoriesusing dika fat (DF) from Irvingia gabonensis seeds as a base comparatively with both water and fatty soluble bases. Rectalsuppositories containing promethazine hydrochloride (25 mg) in pre-calibrated mould were prepared by fusionmethod using DF, macrogol (MG), cocoa butter (CB) and cocoa butter + 10%w/w (weight by weight) beeswax (CBW)as bases. Thereafter the suppositories were characterized using parameters such as appearance, crushing strength,weight variation, melting point, pH, liquefaction time, content uniformity, and in vitro release in accordance withstandard procedures. Results obtained indicated that the bases used generally could be ranked in the order of DF > CB> MG > CBW in terms of favourable physicochemical properties investigated. The foregoing indicates that DF haspromising potential and could be a substitute suppository base in the formulation of promethazine hydrochloridesuppositories.