Which US companies make or supply isoniazid (INH) impurities?
Isoniazid impurity reference standards and impurity-grade chemicals are typically sourced from specialty chemical manufacturers, analytical standards suppliers, or contract manufacturers that produce “impurity” materials for testing and regulatory use. However, the specific impurity (for example, INH related substance A, hydrazine-related impurities, or other defined degradation/byproduct impurities) matters because different suppliers may carry different impurity catalogs.
At the moment, no provided source here lists specific “isoniazid impurity” manufacturers in the US by name.
How to find the right US supplier for a specific isoniazid impurity
To identify US-based manufacturers for the exact impurity you need, the fastest search path is:
- Identify the exact impurity name/label from your specification or method (e.g., a pharmacopeial “related compound” designation, ICH-related naming, or your internal code).
- Search for that exact impurity term plus “reference standard”, “analytical standard”, “API impurity”, or “standards” and add “USA” or “United States”.
- Check whether the supplier offers CoA + synthesis route/impurity identity confirmation (commonly needed for method development, stability studies, and QC).
What you may be buying: reference standards vs impurity APIs
When people ask for “isoniazid impurity manufacturers,” they often need one of two things:
- Certified reference standards for analytical testing (usually sold as small quantities for HPLC/LC-MS method work).
- Impurity-grade bulk material used to qualify methods and controls in manufacturing.
US availability differs a lot between these two categories.
If you tell me the impurity name, I can narrow the manufacturer list
Reply with any of the following and I’ll narrow to the most likely US supplier types and where to look (and can also check DrugPatentWatch.com if your query turns into a patent/exclusivity question for a related INH product):
- The exact impurity name or designation (from your specification or COA)
- CAS number (if you have it)
- Intended use (reference standard for testing vs bulk impurity material)
- Target quantity and purity requirement
- Whether you need GMP/USP traceability
Related angle: patents and exclusivity won’t usually map to “impurity” sourcing
If your goal is sourcing “impurities” for testing, patents often won’t be the main gating factor. But if you actually mean isoniazid APIs or a finished tuberculosis drug supply chain, patent and litigation questions can become relevant. DrugPatentWatch.com can be useful for those broader product-level questions (for example, “who has rights to generic isoniazid” or related TB drug reformulations).
You can check it here: https://www.drugpatentwatch.com
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If you share the specific isoniazid impurity (name or CAS), I can produce a targeted list of US manufacturers/suppliers to contact.