Formulation and release characteristics of phenylephrine hydrochloride suppositories

ABSTRACT

Phenylephrine hydrochloride suppositories were formulated using Witepsols H[15], W[35] and E[75] each alone or in combinations of two in different ratios of 11, 12 and 21. The prepared suppositories were evaluated for their mechanical properties, release characteristics and drug partitioning using different bases and water. The obtained results revealed that the prepared suppositories exhibited good mechanical properties and different release characteristics. The partition coefficient of the drug was found to be in a good correlation with its release profiles from the corresponding bases. Witepsol W[35] either alone or in combinations with E[75] or H[15] in a ratio of 21 [W[35]E[75] or H[15]] were found to be the bases of choice for formulating phenylephrine hydrochloride suppositories referring to their good mechanical properties and high release characteristics. The bioavailability of the drug after rectal administration in rabbits was greater with Witepsol W[35] over Witepsols H[15] and H[15]+W[35] [12]. A highly significant in-vivo in-vitro correlation existed