Nitrosamine impurities

Since 2018, elevated levels of nitrosamine impurities – a probable carcinogen – have been found in some commonly prescribed medicines such as blood pressure medications, antacids, diabetes drugs, and smoking cessation medicines. Nitrosamines are in the news once again; more recent drug recalls have resulted from the detection in certain medicines of drug substance-related nitrosamine impurities, a sub-category of nitrosamines with chemical structures resembling those of active pharmaceutical ingredients.

Nitrosamines can form in a lot of different ways. To ensure drug product quality, manufacturers must properly assess the risk of nitrosamine formation in their products and further investigate any potential risks. While product recalls are concerning, this is part of the process to overcome the challenge of nitrosamines and work to eliminate them from our drug supply.

To protect patients and strengthen the global medicines supply chain, USP is supporting manufacturers and regulators with standards, tools and solutions for testing, assessing risk and understanding potential sources related to nitrosamine impurities. USP also has created a fast-growing online community known as Nitrosamines Exchange where manufacturers and other stakeholders are having real-time conversations and learning from one another about challenges they face with nitrosamine impurities.

scientists talking about nitrosamine impurities
scientists talking about nitrosamine impurities

Nitrosamines Analytical Hub

Online repository containing non-compendial analytical procedures (analytical notes) for testing nitrosamine impurities and related substances.

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Perspectives from USP about nitrosamine impurities

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A pharma mystery: Cancer-causing impurities drive joint search for answers
Nitrosamine impurities in medicines—What’s the risk?
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Safeguarding patient health through the work of USP scientists and volunteer experts

Standards, tests and tools from USP support manufacturers and regulators in assessing the risk of nitrosamine impurities.

nitrosamine impurities reference standards
Control Nitrosamines Impurities with These Eight Reference Standards

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Standards | Process | Service

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nitrosamine impurities general chapter
New GC 1469 Nitrosamine Impurities

To protect patients from adverse effects of nitrosamines as impurities, USP has developed a new general chapter to provide information useful for ensuring the appropriate control of nitrosamine impurities in drug substances and drug products.

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