Science-based solutions for controlling nitrosamine impurities in medicines

Nitrosamines have been in the news since 2018, when elevated levels of nitrosamines – a probable carcinogen – were detected in several blood pressure medications. Since then, elevated levels of nitrosamines have been found in some other commonly prescribed medicines such as antacids, diabetes drugs, and smoking cessation medicines, to name a few.

Not only do nitrosamines pose a risk of physical harm to patients, but they can result in marketplace disruptions including product recalls, withdrawals, and even drug shortages. Nitrosamine impurities in medicines can also undermine trust in medicine quality, harming patients who may be reluctant to take the medicines they need to stay healthy.

Nitrosamine Drug-Substance Related Impurities (NDSRIs) have further complicated the issue, due to the lack of availability of toxicity data and acceptable intake limits, creating new challenges to keep up with.

Nitrosamines can form in medicines in a lot of different ways, presenting industries and regulators around the globe with challenges with both detection and control. Prioritizing quality earlier in the manufacturing process can help maximize efficiency, manage costs, reduce risks and protect patients.

USP is supporting manufacturers and regulators with proven science-based tools and solutions for testing, assessing risk and identifying potential sources related to nitrosamines. USP is also providing educational resources and ways to connect with and learn from experts in the field and others tackling similar nitrosamine challenges.

USP Nitrosamine-Related Solutions

• USP General Chapter <1469> Nitrosamine Impurities provides information on developing testing methodologies to detect and measure nitrosamine impurities in drug ingredients and drug products.

• USP’s official Reference Standards and Pharmaceutical Analytical Impurities are physical samples that can serve as a benchmark for impurity analysis.

• USP Education resources provide practical information on sources of nitrosamine impurities in drugs as well as strategies for controlling them in both live and self-paced courses.

• USP’s Nitrosamines Exchange is a fast-growing online community where manufacturers and others around the globe connect in real-time conversations and learn from one another about challenges they face with nitrosamine impurities.

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


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