NSF/ANSI 455-4 Audits for OTC Manufacturers

NSF/ANSI 455-4 is an American National Standard developed through the ANSI consensus driven process that is specific to assess Good Manufacturing Practice (GMP) compliance at OTC drug manufacturing facilities. The scheme applies to facilities involved in the manufacturing, packaging, warehousing and distribution of OTC products.

The standard is designed for products that will be sold in the U.S. and Canadian markets. It provides a structured, independent audit framework that aligns with FDA expectations for OTC drugs under 21 CFR 210/211 while offering a practical approach to quality assurance.

As OTC products face increasing regulatory scrutiny, retailer expectations, and consumer demand for safety and transparency, Intertek’s NSF/ANSI 455-4 audit services help manufacturers demonstrate robust GMP compliance, supporting FDA readiness and brand confidence.

The Global Retailer and Manufacturer Alliance (GRMA) is the Certification Program Owner (CPO) for the NSF ANSI 455 standards and recognizes the NSF/ANSI 455 standards as part of its publicly accredited certification program, providing dual-level audit oversight and a common grading scheme accepted across major U.S. retailers.

NSF/ANSI 455-4 is part of the broader NSF/ANSI 455 portfolio of standards, which also includes NSF/ANSI 455-3 for cosmetics and personal care products and NSF/ANSI 455-2 for dietary supplements.

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What Is NSF/ANSI 455-4?

NSF/ANSI 455-4 is an accredited audit standard developed through the American National Standards Institute (ANSI) consensus process to assess GMP compliance for OTC drug manufacturing facilities. It is one of three standards in the NSF/ANSI 455 portfolio, alongside 455-2 for dietary supplements and 455-3 for cosmetics, and is owned by the Global Retailer and Manufacturer Alliance (GRMA).

The standard supports organizations operating at the intersection of pharmaceuticals, dietary supplements, and cosmetics. At its foundation are the core FDA regulations including 21 CFR 210/211 and ICH Q10, combined with additional retailer quality requirements developed through industry consensus.

For North American Manufacturers

• Independent, third-party verification of OTC GMP compliance
• Direct alignment with FDA expectations for OTC drugs (21 CFR 210/211)
• A consistent audit framework across multi-product facilities manufacturing pharmaceuticals, cosmetics, and dietary supplements
• Increased confidence for retailers, brand partners, and regulators

Why NSF/ANSI 455-4 Matters in North America

OTC manufacturers in the U.S. and Canada operate in a complex regulatory environment where expectations extend beyond FDA inspections alone. Retailers, brand owners, and private-label partners increasingly require third-party GMP audits to validate quality and compliance before onboarding suppliers.

NSF/ANSI 455-4 certification helps organizations:

• Demonstrate proactive compliance beyond minimum regulatory requirements
• Support supplier qualification and streamline retailer onboarding
• Strengthen internal quality systems with a risk-based, continuous-improvement approach
• Prepare for FDA inspections and regulatory inquiries
• Protect brand reputation and build consumer trust
• Reduce audit redundancy, a single GRMA-recognized audit accepted by multiple major retailers

The Intertek Advantage

As a trusted global assurance provider and authorized GRMA certification body, Intertek brings deep North American regulatory expertise combined with local audit delivery. 

Our independent auditors bring extensive industry experience and objective evaluation to every process they assess, supported by advanced quality management methodologies.