Question

g basis. A topical gel contains 2.5% w/w clindamycin phosphate and 0.035% w/w tretinoin. Calculate the quantity of clindamycin phosphate on an m OA. 35 mg/g B, 2.5 mg/g 0C.25 mg/g D.0.35 mg/g

Answer 1

Percentage weight in weight (w/w) expresses the number of grams of a constituent in 100g of the solution or preparation.

It is expressed as %ww

Solid or semisolid components in solid or semisolid preparation have weight-in-weight relationships with calculations following the equation as
'g' of preparation / % concentration ^a = g of component

In this calculation, percentage concentration is expressed as decimally eg: 2.5% and 0.035%

A topical gel contains 2.5% w/w clindamycin phosphate and 0,035% w/w tretinoin.

Thus we can express the quantity of clindamycin is 25mg/g and 0.35mg/g of tretinoin.

So here the quantity of clindamycin phosphate on mg/g basis is 25,

So the answer is 25mg/g of clindamycin phosphate