Hyoscyamine Hydrobromide
(hye'' oh sye' a meen hye'' droe broe' mide).
C17H23NO3·HBr 370.28

Benzeneacetic acid, -(hydroxymethyl)-, 8-methyl-8-azabicyclo[3.2.1]oct-3-yl ester, hydrobromide [3(S)-endo]-.

1h,5h-Tropan-3-ol ()-tropate (ester) hydrobromide [306-03-6].
» Hyoscyamine Hydrobromide contains not less than 98.5 percent and not more than 100.5 percent of C17H23NO3·HBr, calculated on the dried basis. [Caution—Handle Hyoscyamine Hydrobromide with exceptional care, since it is highly potent. ]
Packaging and storage— Preserve in tight, light-resistant containers.
USP Reference standards 11
USP Hyoscyamine Sulfate RS Click to View Structure
A: Transfer 30 mg of Hyoscyamine Hydrobromide and 36 mg of USP Hyoscyamine Sulfate RS to individual 60-mL separators with the aid of 5-mL portions of water. To each separator add 1.5 mL of 1 N sodium hydroxide and 10 mL of chloroform. Shake for 1 minute, allow the layers to separate, and filter the chloroform extracts through separate filters of about 2 g of anhydrous granular sodium sulfate supported on pledgets of glass wool. Extract each aqueous layer with two additional 10-mL portions of chloroform, filtering and combining with the respective main extracts. Evaporate the chloroform solutions under reduced pressure to dryness, and dissolve each residue in 10 mL of carbon disulfide: the IR absorption spectrum, determined in a 1-mm cell, of the solution obtained from the test specimen exhibits maxima only at the same wavelengths as that of the solution obtained from the Reference Standard.
B: To about 1 mL of a solution (1 in 20) add gold chloride TS, dropwise with shaking, until a definite precipitate separates. Add a small amount of 3 N hydrochloric acid, dissolve the precipitate with the aid of heat, and allow the solution to cool: lustrous reddish brown scales that may be accompanied by reddish brown needles are formed (distinction from atropine and scopolamine).
C: To an aqueous solution (1 in 20) add silver nitrate TS: a yellowish-white precipitate is formed, and it is insoluble in nitric acid.
Melting temperature 741: not less than 149.
Specific rotation 781S: not less than 24.
Test solution: 50 mg per mL, in water.
Loss on drying 731 Dry it at 105 for 2 hours: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.2%.
Other alkaloids— Dissolve 250 mg in 1 mL of 0.1 N hydrochloric acid, and dilute with water to 15 mL. To 5 mL of the solution add a few drops of platinic chloride TS: no precipitate is formed immediately. To another 5-mL portion add 2 mL of 6 N ammonium hydroxide: the mixture may develop a slight opalescence, but no turbidity or precipitate is formed immediately.
Assay— Dissolve about 700 mg of Hyoscyamine Hydrobromide, accurately weighed, in a mixture of 50 mL of glacial acetic acid and 10 mL of mercuric acetate TS. Add 1 drop of crystal violet TS, and titrate with 0.1 N perchloric acid VS to a blue-green endpoint. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 37.03 mg of C17H23NO3·HBr.
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Topic/Question Contact Expert Committee
Monograph Elena Gonikberg, Ph.D.
Principal Scientific Liaison
(SM32010) Monographs - Small Molecules 3
Reference Standards RS Technical Services
USP35–NF30 Page 3464