Phosphate Topical Gel

Clindamycin phosphate is a water-soluble ester of the semisynthetic antibiotic produced by a 7(S)-chloro- substitution of the 7(R)-hydroxyl group of the parent antibiotic lincomycin. Chemically, clindamycin phosphate is (C18H34CIN208PS). The topical gel also contains benzoyl 

While continuing to mix, add carbopol 941 slowly to step above, avoiding clumping. 

Mix vigorously at room temperature until a uniform and lump-free dispersion is achieved. 

While mixing, add sufficient sodium hydroxide, 10% solution, to achieve a pH of 5.3-5.7. Mix until uniform. 

Add the remaining water to make 100% and mix until uniform. Please note that a commercial preparation contains an additional component allantoin. 

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