Ondansetron Hydrochloride, commonly referred to as Ondansetron HCl, is an important pharmaceutical active ingredient belonging to the 5-HT3 serotonin receptor antagonist class. It is widely used in pharmaceutical formulations designed to prevent and control nausea and vomiting associated with chemotherapy, radiotherapy and surgery. The pharmaceutical substance is commonly supplied as Ondansetron Hydrochloride Dihydrate, a crystalline hydrochloride salt of the racemic form of ondansetron. FDA documentation identifies Ondansetron Hydrochloride as the active ingredient in several pharmaceutical products and describes it as a selective blocking agent of the serotonin 5-HT3 receptor.
Ondansetron HCl API is identified by CAS Number 103639-04-9 and has the empirical formula C18H19N3O·HCl·2H2O. The molecular weight of the dihydrate is approximately 365.86 g/mol. FDA's Global Substance Registration System identifies the ingredient under UNII NMH84OZK2B. The same FDA record lists Ondansetron Hydrochloride Dihydrate and Ondansetron HCl among its recognized synonyms.
Ondansetron Hydrochloride is chemically described as (±)-2,3-dihydro-9-methyl-3-[(2-methylimidazol-1-yl)methyl]carbazol-4(1H)-one monohydrochloride dihydrate. It is a hydrochloride salt containing two molecules of water of crystallization. The presence of the dihydrate form is important when calculating molecular mass and when defining pharmaceutical specifications for the API.
The USP-NF monograph identifies the substance as Ondansetron Hydrochloride, with the formula C18H19N3O·HCl·2H2O and molecular mass 365.86. USP defines the substance as containing not less than 98.0% and not more than 102.0% of ondansetron hydrochloride, calculated on the anhydrous basis.
FDA describes Ondansetron Hydrochloride Dihydrate as a white to off-white powder that is soluble in water and normal saline. This physical property supports its use in pharmaceutical dosage forms, including oral and parenteral products.
Ondansetron is pharmacologically important because it selectively blocks the 5-hydroxytryptamine type 3 (5-HT3) receptor. Serotonin released in response to certain chemotherapy agents and other stimuli can activate 5-HT3 receptors involved in the vomiting reflex. Blocking these receptors provides a pharmacological approach to preventing nausea and vomiting.
The pharmaceutical relevance of Ondansetron HCl extends across several dosage forms. It is used in tablets, orally disintegrating preparations, oral solutions and injections. FDA labeling for ondansetron products confirms the use of the hydrochloride dihydrate form as the active ingredient in conventional oral formulations.
Because of its established pharmaceutical application and well-defined chemical identity, Ondansetron HCl Pharmaceutical API is an important ingredient for pharmaceutical formulation and manufacturing programs.
Quality control is a critical consideration when evaluating an Ondansetron HCl API Manufacturer India. The current USP-NF monograph provides specific analytical requirements for identification and assay and includes controls for related substances.
The USP assay requirement is 98.0%–102.0% of Ondansetron Hydrochloride calculated on the anhydrous basis. This calculation basis is particularly important because the official substance is the dihydrate and therefore contains water of crystallization. The assay should not be incorrectly interpreted as 98.0%–102.0% of the total hydrated material without considering the specified calculation basis.
USP identification includes infrared spectroscopy, a chemical identification test for chloride and chromatographic comparison of the major peak with the standard used in the assay. This provides multiple complementary approaches for confirming the identity of the API.
Related-substance control is an important component of Ondansetron HCl API quality evaluation. The USP-NF monograph identifies reference standards for Ondansetron Related Compound A, Related Compound C, Related Compound D and the Ondansetron Resolution Mixture, demonstrating the importance of chromatographic impurity and stereochemical evaluation.
For commercial pharmaceutical manufacturing, the complete impurity profile should be evaluated according to the applicable approved specification and validated analytical method. Batch-specific chromatographic data are particularly useful when assessing the quality and consistency of Ondansetron Hydrochloride API.
Ondansetron HCl Bulk API is relevant to pharmaceutical manufacturers producing dosage forms containing ondansetron hydrochloride. The material may be used in formulation-development programs, analytical research and commercial pharmaceutical manufacturing, depending on the intended application and applicable regulatory requirements.
Because Ondansetron HCl is normally encountered as a dihydrate, procurement specifications should clearly identify the dihydrate form and CAS 103639-04-9. This helps avoid confusion with Ondansetron base, which has a different molecular weight and chemical identity. FDA records Ondansetron itself separately with the molecular formula C18H19N3O and molecular weight 293.36 g/mol.
India is an established pharmaceutical manufacturing market with significant capabilities in active pharmaceutical ingredients and finished pharmaceutical formulations. Organizations searching for an Ondansetron HCl API Manufacturer India may evaluate manufacturers based on manufacturing consistency, analytical capabilities, quality systems, documentation and regulatory suitability.
A reliable Ondansetron HCl Manufacturer India should provide clear technical identification of the material, including the product name, CAS Number, molecular formula, molecular weight, grade, pharmacopoeial status and applicable specification.
The use of CAS Number 103639-04-9 is particularly useful when communicating procurement requirements because FDA GSRS specifically maps this CAS number to Ondansetron Hydrochloride Dihydrate.
Technical documentation is an important part of pharmaceutical API evaluation. Documentation for Ondansetron HCl Pharmaceutical API can include product specifications, batch-specific Certificate of Analysis, identification results, assay, related-substance profile, water content, residual-solvent information where applicable, elemental-impurity assessment and Safety Data Sheet.
The API should be evaluated against the applicable pharmacopoeial and regulatory requirements for the intended market. USP-NF currently provides a dedicated Ondansetron Hydrochloride monograph, making USP compliance a useful quality reference for pharmaceutical applications.
One of the most important technical aspects of Ondansetron HCl is distinguishing the hydrochloride dihydrate from the free base. Ondansetron base has a molecular weight of 293.36 g/mol, whereas Ondansetron Hydrochloride Dihydrate has a molecular weight of approximately 365.86 g/mol.
This difference results from both hydrochloride salt formation and the presence of two water molecules in the crystalline substance. Therefore, pharmaceutical specifications, purchase orders and technical documents should clearly identify the required form as Ondansetron Hydrochloride Dihydrate when that is the intended API.
For organizations evaluating an Ondansetron HCl API Supplier India, quality should be considered across chemical identity, assay, impurity control, physical characteristics and documentation. USP's current monograph provides a recognized framework for identification and assay of Ondansetron Hydrochloride.
The USP assay range of 98.0%–102.0% on the anhydrous basis is a particularly important numerical specification for CMS data. Other quality attributes should be entered from the applicable approved specification rather than using generic API values. This approach avoids incorrectly assigning specifications from unrelated APIs or from Ondansetron base.
Ondansetron Hydrochloride is a well-established pharmaceutical API belonging to the 5-HT3 receptor antagonist class. It is commonly supplied as the dihydrate, with CAS Number 103639-04-9, empirical formula C18H19N3O·HCl·2H2O, and molecular weight approximately 365.86 g/mol.
For companies searching for Ondansetron HCl API Manufacturer in India, Ondansetron HCl API Supplier, Ondansetron HCl API Supplier India, Ondansetron Pharmaceutical API, or Ondansetron Bulk API, accurate identification of the hydrochloride dihydrate form is essential.
The USP-NF monograph provides a defined assay requirement of 98.0%–102.0% calculated on the anhydrous basis, together with established identification procedures and related-compound reference standards.
With its established pharmaceutical application, recognized pharmacopoeial monograph and clearly defined chemical identity, Ondansetron HCl API remains an important active pharmaceutical ingredient for pharmaceutical development and manufacturing.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 0.5% |
| Residue on Ignition | NMT 0.2% |
| Individual Impurity | NMT 0.10% |
| Total Impurities | NMT 0.50% |