Packaging and storage—
Preserve in single-dose or in multiple-dose containers, preferably of Type I glass.
Identification—
A:
To 1 mL of Injection add 1 drop of 3 N hydrochloric acid and 2 drops of
ferric chloride TS. Heat to boiling, and add 1 mL of potassium ferricyanide solution (1 in 200): a blue-green color develops.
Other requirements—
It meets the requirements under
Injections 
1
.
Assay—
Transfer an accurately measured volume of Injection, equivalent to about 40 mg of levorphanol tartrate, to a 125-mL separator. Add 5 g of sodium chloride and sufficient sodium bicarbonate to render the solution alkaline to litmus, add an additional 100 mg of sodium bicarbonate, and extract the levorphanol with five 20-mL portions of a mixture of 3 volumes of ether and 1 volume of chloroform. Pass the combined extracts through a layer of about 10 g of granular anhydrous sodium sulfate into a 500-mL conical flask, and evaporate to a volume of about 30 mL. Add about 50 mL of chloroform and 1 drop of methanolic methyl red TS, and titrate with 0.01 N perchloric acid in dioxane VS to a red endpoint. Perform a blank determination, and make any necessary correction. Each mL of 0.01 N perchloric acid is equivalent to 4.435 mg of C17H23NO·C4H6O6·2H2O.
