Rx

Ephedrine Hydrochloride--------------- 0.5
Chlorobutanol -------------------------------0.25
Dextrose, monohydrate q.s.
Rose Water ad. -------------------------------50
Make isoton. sol.
Sig. Nose drops.
How many grams of dextrose monohydrate should be used in compounding
the prescription? (hint; the NaCl equivalent for Ephedrine Hydrochloride
0.29, for Chlorobutanol is 0.24 and for dextrose monohydrate is 0.16)

The total NaCl equivalent of the prescription is 0.79 (0.29 + 0.24 + 0.16). To make an isotonic solution, the total amount of dextrose monohydrate needed is 50 grams (50 x 0.16 = 0.79). Therefore, the total amount of dextrose monohydrate needed to compound the prescription is 50 grams.