MUCOADHESIVE EFFECT OF CARBOPOL ON DRUG RELEASE RATE FROM DOUBLE PHASED SUPPOSITORIES

Abstract

Suppositor ies are the reliable alternat ive dosage form for pat ients at home or exper iencing frequent
attacks of hypertension and angina pectoris. Propranolol hydrochloride, a selective ß- adrenergic antagonist
used in the t reatment of hyper tension and angina pector is, which undergoes extensive hepat ic
metabolism, has been formulated as suppositories. In order to restrict the drug absorption to only the
lower rectum, mucoadhesive Propranolol hydrochloride suppositories were prepared using cocoa butter
as a base, carbopol 934P and white bees wax as additives. Carbopol has a mucoadhesive property and
beeswax gives the required stiffness to the suppositories. The effect of these additives on the physicochemical
behavior and drug release rates from the suppositories were studied. Beeswax at higher concentration
considerably increased the melting point and hardness of the base whereas carbopol showed
lit t le effect on the melt ing point of the base. The drug release profile indicated that with decreased
carbopol concentration (2 %w/w) the release rate was increased. These findings suggest that carbopol
can be used not only as a release rate enhancer but also as a mucoadhesive mater ial to prevent the
suppositories moving to the upper rectum susceptible to first pass metabolism