ENTOCORT EC- budesonide capsule
Prometheus Laboratories Inc
DESCRIPTION SECTION
Budesonide, the active ingredient of ENTOCORT� EC capsules, is a synthetic corticosteroid. It is designated chemically as (RS)-11?, 16?, 17,21-tetrahydroxypregna-1,4-diene-3,20-dione cyclic 16,17-acetal with butyraldehyde. Budesonide is provided as a mixture of two epimers (22R and 22S). The empirical formula of budesonide is C25 H34 O6 and its molecular weight is 430.5. Its structural formula is:
Structural Formula fir Epimer 22R if budesonide
(click image for full-size original)
Structural Formula for Epimer 22S of budesonide
(click image for full-size original)
Budesonide is a white to off-white, tasteless, odorless powder that is practically insoluble in water and heptane, sparingly soluble in ethanol, and freely soluble in chloroform. Its partition coefficient between octanol and water at pH 5 is 1.6 x 103 ionic strength 0.01.
Each capsule contains 3 mg of micronized budesonide with the following inactive ingredients: ethylcellulose, acetyltributyl citrate, methacrylic acid copolymer type C, triethyl citrate, antifoam M, polysorbate 80, talc, and sugar spheres. The capsule shells have the following inactive ingredients: gelatin, iron oxide, and titanium dioxide.
CLINICAL PHARMACOLOGY
Budesonide has a high topical glucocorticosteroid (GCS) activity and a substantial first pass elimination. The formulation contains granules which are coated to protect dissolution in gastric juice, but which dissolve at pH >5.5, ie, normally when the granules reach the duodenum. Thereafter, a matrix of ethylcellulose with budesonide controls the release of the drug into the intestinal lumen in a time-dependent manner.
