Serotonin 5-HT3 antagonist; treatment of nausea and vomiting.<\/p>\n
Preparations <\/strong><\/p>\n Ondansetron Injection Ondansetron Tablets Ph Eur<\/p>\n (3RS)-9-Methyl-3-[(2-methyl-1H-imidazol-1-yl)methyl]-1,2,3,9-tetrahydro-4H-carbazol-4-one hydrochloride dihydrate.<\/p>\n Content<\/strong><\/p>\n 97.5 per cent to 102.0 per cent (anhydrous substance).<\/p>\n Appearance<\/strong><\/p>\n White or almost white powder.<\/p>\n Solubility<\/strong><\/p>\n Sparingly soluble in water, soluble in methanol, sparingly soluble in ethanol (96 per cent), slightly soluble in methylene chloride.<\/p>\n A. Infrared absorption spectrophotometry (2.2.24).<\/p>\n Comparison\u00a0 ondansetron hydrochloride dihydrate CRS.<\/p>\n B. It gives reaction (a) of chlorides (2.3.1).<\/p>\n Thin-layer chromatography (2.2.27).<\/p>\n Solvent mixture\u00a0 concentrated ammonia R, ethanol (96 per cent) R, methanol R (0.5:100:100 V\/V\/V).<\/p>\n Test solution\u00a0 Dissolve 0.125 g of the substance to be examined in the solvent mixture and dilute to 10.0 mL with the solvent mixture.<\/p>\n Reference solution (a)\u00a0 Dissolve 12.5 mg of ondansetron for TLC system suitability CRS (containing impurities A and B) in the solvent mixture and dilute to 1 mL with the solvent mixture.<\/p>\n Reference solution (b)\u00a0 Dilute 1 mL of the test solution to 100 mL with the solvent mixture. Dilute 4.0 mL of this solution to 10.0 mL with the solvent mixture.<\/p>\n Plate\u00a0 TLC silica gel F254 plate R.<\/p>\n Mobile phase\u00a0 concentrated ammonia R, methanol R, ethyl acetate R, methylene chloride R (2:40:50:90 V\/V\/V\/V).<\/p>\n Application\u00a0 20 \u00b5L.<\/p>\n Development\u00a0 Over 3\/4 of the plate.<\/p>\n Drying\u00a0 In air.<\/p>\n Detection\u00a0 Examine in ultraviolet light at 254 nm.<\/p>\n Retardation factors\u00a0 Impurity A = about 0.3; impurity B = about 0.4; ondansetron = about 0.6.<\/p>\n System suitability\u00a0 Reference solution (a):<\/p>\n \u2014 the chromatogram shows 3 clearly separated spots.<\/p>\n Limit:<\/p>\n \u2014 impurity B: any spot due to impurity B is not more intense than the principal spot in the chromatogram obtained with reference solution (b) (0.4 per cent).<\/p>\n Liquid chromatography (2.2.29).<\/p>\n Test solution (a)\u00a0 Dissolve 50.0 mg of the substance to be examined in the mobile phase and dilute to 100.0 mL with the mobile phase.<\/p>\n Test solution (b)\u00a0 Dissolve 90.0 mg of the substance to be examined in the mobile phase and dilute to 100.0 mL with the mobile phase. Dilute 10.0 mL of the solution to 100.0 mL with the mobile phase.<\/p>\n Reference solution (a)\u00a0 Dilute 2.0 mL of test solution (a) to 100.0 mL with the mobile phase. Dilute 10.0 mL of this solution to 100.0 mL with the mobile phase.<\/p>\n Reference solution (b)\u00a0 Dissolve 5.0 mg of ondansetron impurity E CRS and 5 mg of ondansetron impurity A CRS in the mobile phase and dilute to 100.0 mL with the mobile phase.<\/p>\n Reference solution (c)\u00a0 Dissolve 5 mg of ondansetron for LC system suitability CRS (containing impurities C and D) in the mobile phase and dilute to 10 mL with the mobile phase.<\/p>\n Reference solution (d)\u00a0 Dissolve 5.0 mg of ondansetron impurity D CRS in the mobile phase and dilute to 100.0 mL with the mobile phase. Dilute 1.0 mL of the solution to 100.0 mL with the mobile phase.<\/p>\n Reference solution (e)\u00a0 Dissolve 90.0 mg of ondansetron hydrochloride dihydrate CRS in the mobile phase and dilute to 100.0 mL with the mobile phase. Dilute 10.0 mL of the solution to 100.0 mL with the mobile phase.<\/p>\n Reference solution (f)\u00a0 Dissolve 5.0 mg of ondansetron impurity F CRS and 5 mg of ondansetron impurity G CRS in the mobile phase and dilute to 100.0 mL with the mobile phase.<\/p>\n Reference solution (g)\u00a0 To 1.0 mL of reference solution (b) add 1.0 mL of reference solution (f) and dilute to 100.0 mL with the mobile phase.<\/p>\n Column:<\/p>\n \u2014 size: l = 0.25 m, \u00d8 = 4.6 mm;<\/p>\n \u2014 stationary phase: cyanosilyl silica gel for chromatography R (5 \u00b5m).<\/p>\n Mobile phase\u00a0 Mix 20 volumes of acetonitrile R1 and 80 volumes of a 2.8 g\/L solution of sodium dihydrogen phosphate monohydrate R previously adjusted to pH 5.4 with a 40 g\/L solution of sodium hydroxide R.<\/p>\n Flow rate\u00a0 1.5 mL\/min.<\/p>\n Detection\u00a0 Spectrophotometer at 216 nm.<\/p>\n Injection\u00a0 20 \u00b5L of test solution (a) and reference solutions (a), (b), (c), (d), (f) and (g).<\/p>\n Run time\u00a0 1.5 times the retention time of ondansetron.<\/p>\n Identification of impurities:<\/p>\n \u2014 use the chromatogram supplied with ondansetron for LC system suitability CRS and the chromatogram obtained with reference solution (c) to identify the peaks due to impurities C and D;<\/p>\n \u2014 use the chromatogram obtained with reference solution (b) to identify the peaks due to impurities A and E;<\/p>\n \u2014 use the chromatogram obtained with reference solution (f) to identify the peaks due to impurities F and G.<\/p>\n Relative retention\u00a0 With reference to ondansetron (retention time = about 18 min): impurity E = about 0.17; impurity F = about 0.20 (E and F may coelute); impurity C = about 0.35; impurity D = about 0.45; impurity A = about 0.80; impurity G = about 0.89 (A and G may coelute or be inverted).<\/p>\n System suitability\u00a0 Reference solution (c):<\/p>\n \u2014 resolution: minimum 2.5 between the peaks due to impurities C and D.<\/p>\n Limits:<\/p>\n \u2014 correction factor: for the calculation of content, multiply the peak area of impurity C by 0.6;<\/p>\n \u2014 impurity C: not more than the area of the principal peak in the chromatogram obtained with reference solution (a) (0.2 per cent);<\/p>\n \u2014 sum of impurities A and G: not more than the area of the principal peak in the chromatogram obtained with reference solution (a) (0.2 per cent);<\/p>\n \u2014 sum of impurities E and F: not more than the sum of the areas of the corresponding peaks in the chromatogram obtained with reference solution (g) (0.2 per cent);<\/p>\n \u2014 impurity D: not more than 1.5 times the area of the principal peak in the chromatogram obtained with reference solution (d) (0.15 per cent);<\/p>\n \u2014 unspecified impurities: for each impurity, not more than 0.5 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.10 per cent);<\/p>\n \u2014 total: maximum 0.4 per cent;<\/p>\n \u2014 disregard limit: 0.25 times the area of the principal peak in the chromatogram obtained with reference solution (a) (0.05 per cent).<\/p>\n Water (2.5.12)<\/strong><\/p>\n 9.0 per cent to 10.5 per cent, determined on 0.200 g.<\/p>\n Sulfated ash (2.4.14)<\/strong><\/p>\n Maximum 0.1 per cent, determined on 1.0 g.<\/p>\n Liquid chromatography (2.2.29) as described in the test for related substances with the following modifications.<\/p>\n Injection\u00a0 Test solution (b) and reference solution (e).<\/p>\n System suitability\u00a0 Reference solution (e):<\/p>\n \u2014 symmetry factor: maximum 2.5 for the peak due to ondansetron.<\/p>\n Calculate the percentage content of C18<\/sub>H20<\/sub>ClN3<\/sub>O taking into account the assigned content of ondansetron hydrochloride dihydrate CRS.<\/p>\n IMPURITIES<\/p>\n Specified impurities\u00a0 A, B, C, D, E, F, G.<\/em><\/p>\n Other detectable impurities (the following substances would, if present at a sufficient level, be detected by one or other of the tests in the monograph. They are limited by the general acceptance criterion for other\/unspecified impurities and\/or by the general monograph Substances for pharmaceutical use (2034). It is therefore not necessary to identify these impurities for demonstration of compliance. See also 5.10.<\/em><\/p>\n Control of impurities in substances for pharmaceutical use)\u00a0 H.<\/em><\/p>\n A. (3RS)-3-[(dimethylamino)methyl]-9-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-one,<\/p>\n B. 6,6\u2032-methylenebis[(3\u039e)-9-methyl-3-[(2-methyl-1H-imidazol-1-yl)methyl]-1,2,3,9-tetrahydro-4H-carbazol- 4-one],<\/p>\n C. 9-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-one,<\/p>\n D. 9-methyl-3-methylidene-1,2,3,9-tetrahydro-4H-carbazol-4-one,<\/p>\n E. 1H-imidazole,<\/p>\n F. 2-methyl-1H-imidazole,<\/p>\n G. (3RS)-3-[(1H-imidazol-1-yl)methyl]-9-methyl-1,2,3,9-tetrahydro-4H-carbazol-4-one (C- demethylondansetron),<\/p>\n H. (3RS)-3-[(2-methyl-1H-imidazol-1-yl)methyl]-1,2,3,9-tetrahydro-4H-carbazol-4-one (N- demethylondansetron).<\/p>\n Ph Eur<\/p>\n","protected":false},"excerpt":{"rendered":" Edition: BP 2025 (Ph. Eur. 11.6 update) Action and use Serotonin 5-HT3 antagonist; treatment of nausea and vomiting. Preparations Ondansetron Injection Ondansetron Tablets Ph Eur DEFINITION (3RS)-9-Methyl-3-[(2-methyl-1H-imidazol-1-yl)methyl]-1,2,3,9-tetrahydro-4H-carbazol-4-one hydrochloride dihydrate. Content 97.5 per cent to 102.0 per cent (anhydrous substance). CHARACTERS Appearance White or almost white powder. Solubility Sparingly soluble in water, soluble in methanol, sparingly…<\/p>\n","protected":false},"author":5,"featured_media":26568,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[174],"tags":[],"class_list":["post-26566","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicinal-substances"],"acf":[],"_links":{"self":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26566","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/comments?post=26566"}],"version-history":[{"count":4,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26566\/revisions"}],"predecessor-version":[{"id":27340,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/posts\/26566\/revisions\/27340"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media\/26568"}],"wp:attachment":[{"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/media?parent=26566"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/categories?post=26566"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/nhathuocngocanh.com\/bp\/wp-json\/wp\/v2\/tags?post=26566"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}DEFINITION<\/h2>\n
CHARACTERS<\/h2>\n
IDENTIFICATION<\/h2>\n
TESTS<\/h2>\n
Impurity B<\/h3>\n
Related substances<\/h3>\n
ASSAY<\/h2>\n
STORAGE<\/h2>\n
Protected from light.<\/h2>\n
![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-1.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-2.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-3.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-4.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-5.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-6.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-7.jpg\")
<\/p>\n![\"Ondansetron](\"https:\/\/nhathuocngocanh.com\/bp\/wp-content\/uploads\/2025\/11\/Ondansetron-Hydrochloride-Dihydrate-British-Pharmacopoeia-2025-8.jpg\")
<\/p>\n
\n