Cyclizine Hydrochloride
(sye' kli zeen hye'' droe klor' ide).
C18H22N2·HCl 302.84

Piperazine, 1-(diphenylmethyl)-4-methyl-, monohydrochloride.
1-(Diphenylmethyl)-4-methylpiperazine monohydrochloride [303-25-3].
» Cyclizine Hydrochloride contains not less than 98.0 percent and not more than 100.5 percent of C18H22N2·HCl, calculated on the dried basis.
Packaging and storage— Preserve in tight, light-resistant containers.
USP Reference standards 11
USP Cyclizine Hydrochloride RS Click to View Structure
B: Dissolve 500 mg in 10 mL of a mixture of 3 volumes of alcohol and 2 volumes of water, warming if necessary. Cool the solution in an ice bath, add 1 mL of 1 N sodium hydroxide and 20 mL of water, stir, and filter: the precipitate of the base so obtained, washed with water and dried in vacuum at 60 for 2 hours, melts between 106 and 109.
C: It responds to the tests for Chloride 191.
pH 791: between 4.5 and 5.5, determined potentiometrically in a 1 in 50 solution, the solvent being a mixture of 2 volumes of alcohol and 3 volumes of water.
Loss on drying 731 Dry it at 120 for 3 hours: it loses not more than 1.0% of its weight.
Residue on ignition 281: not more than 0.2%.
Ordinary impurities 466
Test solution: methanol.
Standard solution: methanol.
Eluant: a mixture of chloroform, methanol, and ammonium hydroxide (80:20:1).
Visualization: 2.
Assay— Transfer to a beaker about 400 mg of Cyclizine Hydrochloride, accurately weighed, and dissolve in 80 mL of glacial acetic acid. Add 10 mL of mercuric acetate TS, and titrate with 0.1 N perchloric acid VS, determining the endpoint potentiometrically. Perform a blank determination, and make any necessary correction. Each mL of 0.1 N perchloric acid is equivalent to 15.14 mg of C18H22N2·HCl.
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Monograph Elena Gonikberg, Ph.D.
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(SM32010) Monographs - Small Molecules 3
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