GMP Procedures: Considerations for Manufacturers

September 4, 2012 By


Since the final good manufacturing practices (GMP) rule for dietary supplements was implemented in 2007, the Food and Drug Administration (FDA) has made it very clear that GMP inspections should be a major priority for dietary supplement manufacturers. As evidenced by the number of violations uncovered to date, there has been a severe lack of procedures in place to ensure the quality of the manufactured product.

The new protocols will provide to manufacturers the comprehensive elements needed to have a fully compliant GMP system in place. Every aspect of the manufacturing process should have an accompanying Standard Operating Procedure (SOP) in place, including:

  • Personnel
  • Requirements for the cleaning and sterility of equipment and utensils
  • Process control systems for the varying stages of manufacture
  • Proper packaging, labeling, and storage conditions
  • Master Manufacturing Records (MMRs) and batch records
  • Process for dealing with product complaints
  • Complete recordkeeping

Under the GMP rules, it is the manufacturer’s responsibility to ensure that third-party contractors hired for additional work conduct their operations in accordance with GMPs. Third parties can include contract manufacturers and third-party testing laboratories, and should be reviewed in advance by manufacturers to confirm that they have processes in place to ensure the quality of their work, including the appropriate test methods for the product.

The GMPs for dietary supplements specify that test methods should be scientifically valid, referring to their ability to repeatedly deliver reliable results. Although there are many validated methods available for contract or in-house testing, many times these methods may have been developed for, and validated by, a specific food product, and are not necessarily adaptable to dietary supplements. Even with accredited methods, such as those found in Association of Official Analytical Chemists (AOAC), pharmacopeias, or compendiums, the testing facility must verify that these methods are appropriate for their products.

When using a contract laboratory, a manufacturer can ensure the competency of the lab by reviewing their processes and SOPs that would affect the consistency of the test results, and by scheduling an on-site visit to the testing facility. The manufacturer needs to show that it did its due diligence with their chosen lab, and to be certain that the laboratory was capable of properly testing raw materials and finished products. It is important to keep in mind that it may be difficult to find one lab that is able to perform the full spectrum of tests required. When choosing testing labs, be sure to determine the specialty of each. This screening will ensure that the finished product is efficacious, safe and consistently of high quality.

While there is a definite action towards compliance within the manufacturing and testing of dietary supplements, there are still those that rely on falsifying data in lieu of proper testing. In order to determine if this practice is going on, it is advisable for manufacturers to provide the lab with known samples to see if the lab’s data matches up with the known results. Some samples that would be helpful in this screening would be:

  • Purchasing a reference standard (a highly characterized material) and send only the sample the lab. Ask the lab to identify the purity of the reference standard material to see if it can accurately confirm the material’s concentration.
  • Requesting the lab to test for the presence of a different compound, one that the manufacturer knows should not be present. If the laboratory reports not finding that compound, then that is a good indication of their honesty.
  • Having the lab test a finished product for which the manufacturer knows the amount of the ingredients present, and compare the data with the lab’s analysis.

Since GMP standards are now permeating throughout the entire product life cycle, the compliance of dietary supplements is increasing, providing greater security to consumers. Manufacturers will benefit from the confidence that their products are produced and tested to the highest standards when it comes to health.

dicentra’s qualified staff can provide consultation and work with you to develop SOPs appropriate to your facility, as well as to educate your employees on the importance of following these essential procedures.


dicentra provides regulatory and scientific solutions for accelerated business growth. We specialize in the areas of natural health products, dietary supplements, foods, cosmetics and OTCs. We can be reached at 1-866-647-3279 or at