CORTISPORIN Cream (neomycin and polymyxin B sulfates and hydrocortisone acetate cream, USP) is a topical antibacterial cream. Each gram contains: neomycin sulfate equivalent to 3.5 mg neomycin base, polymyxin B sulfate equivalent to 10,000 polymyxin B units, and hydrocortisone acetate 5 mg (0.5%). The inactive ingredients are liquid petrolatum, white petrolatum, propylene glycol, polyoxyethylene polyoxypropylene compound, emulsifying wax, purified water, and 0.25% methylparaben added as a preservative. Sodium hydroxide or sulfuric acid may be added to adjust pH.
Neomycin sulfate is the sulfate salt of neomycin B and C, which are produced by the growth of Streptomyces fradiae Waksman (Fam. Streptomycetaceae). It has a potency equivalent of not less than 600 µg of neomycin standard per mg, calculated on an anhydrous basis. The structural formulae are:
Polymyxin B sulfate is the sulfate salt of polymyxin B1 and B2, which are produced by the growth of Bacillus polymyxa (Prazmowski) Migula (Fam. Bacillaceae). It has a potency of not less than 6,000 polymyxin B units per mg, calculated on an anhydrous basis. The structural formulae are:
Hydrocortisone acetate is the acetate ester of hydrocortisone, an anti-inflammatory hormone. Its chemical name is 21-(acetyloxy)- 11β,17-dihydroxypregn-4-ene-3,20-dione. Its structural formula is:
The base is a smooth vanishing cream with a pH of approximately 5.0.