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    • A New Level of Brand Protection: Five Things You Need to Know About PDE5 Inhibitor Adulterants

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      Published On Oct 07 2015, 3:40 AM

      The adulteration of dietary supplements with synCovance Supplement Testingthetic phosphodiesterase type 5 (PDE5) inhibitors can cause serious adverse health risks. Covance has introduced a new non-targeted analysis method using liquid chromatography-high resolution mass spectrometry (LC-HRMS) for screening and identification of known and novel PDE5 inhibitors in dietary ingredients and supplements, leading the industry and our clients to a new level of brand protection.

      Below are five things you need to know about PDE5 inhibitors in sexual enhancement supplements and how to screen for these dangerous adulterants.

      1. Some PDE5 inhibitors are FDA-approved drugs

      2. Phosphodiesterase type 5 (PDE5) inhibitors are compounds that can be used for treatment of erectile dysfunction. The use of certain PDE5 inhibitors is approved by the FDA, such as the active ingredients in brand names such as Viagra®, Cialis® and Levitra®. It is only when PDE5 inhibitors are present in over-the-counter sexual enhancement dietary supplements that they are considered adulterants and dangerous for consumers. These adulterants in supplements can take the form of approved PDE5 inhibitors or similar unapproved versions of these drugs called analogues.

      3. PDE5 inhibitor adulterants are common in sexual enhancement supplements

      4. PDE5 inhibitor adulteration of dietary supplements is a serious problem. Over 150 known analogues currently exist outside of the four FDA-approved PDE5 inhibitor drugs. In one study, 81% of 91 herbal products with sexual enhancement claims-but no labeling of synthetic substancesere found to contain synthetic PDE5 inhibitor drugs or an analogue.1 A similar study reported that 77% of 175 illegal sexual enhancement supplements seized contained PDE5 inhibitor adulterants.2

      5. PDE5 inhibitor adulterants can pose a serious health risk

      6. PDE5 inhibitor adulteration in over-the-counter supplements can be dangerous for consumers. When FDA-approved PDE5 inhibitor drugs are prescribed, known drug interactions and side effects are managed by skilled medical care. Manufacturing standards are required and upheld due to regulation and monitoring. Consumers who take over-the-counter sexual enhancement supplements adulterated with PDE5 inhibitors without their knowledge are unknowingly at risk because the side effects, drug interactions and manufacturing processes are not managed, monitored or regulated.

        Many adulterated products have been found to contain PDE5 inhibitor analogues (similar but not approved versions of PDE5 inhibitors). These ingredients present an additional risk because they have not been tested or approved by the FDA, and their side effects and drug interactions are unknown. Additionally, when an ingredient is manufactured for use as an unlabeled adulterant, the manufacturing practices used in production often are not monitored properly or are at a level acceptable for standards.

      7. Manufacturers and retailers of sexual enhancement supplements can help protect their brand by testing for PDE5 inhibitor adulterants

      8. Dietary supplement ingredients and end products with sexual enhancement claims may contain PDE5 inhibitor adulterants. Dietary supplement manufacturers should test ingredients from their suppliers as part of an ongoing vendor verification and supply chain management quality program. Retailers should engage in a statistically sound testing program of all dietary supplement products sold in retail outlets or online as part of an ongoing quality, safety and brand protection program.

      9. Covance has pioneered non-targeted PDE5 inhibitor analysis

      10. To address growing concerns about PDE5 inhibitor adulterants, AOAC International issued a call for methods to screen for these compounds in dietary supplements and ingredients. Covance took action on this issue by responding to the AOAC International call for methods. We have now developed and validated a method using liquid chromatography-high resolution mass spectrometry (LC-HRMS) for non-targeted screening and identification of known and novel PDE5 inhibitors. Accepted by AOAC International as the new First Action Official MethodSM for PDE5 inhibitor analysis in dietary supplements and ingredients, this new testing helps assure the products you market, manufacture or sell uphold your high brand standards. Click here for FAQs regarding PDE5 Inhibitors.


      To discover more about this new offering, contact us today at 1-800-675-8375 or visit our website. Let's start this important conversation.


      1. Campbell, N., Clark, J.P., Stecher, V.J., Thomas, J.W., Callanan, A.C., Donnelly, B.F., Goldstein, I., & Kaminetsky, J.C. (2013) Adulteration of purported herbal and natural sexual performance enhancement dietary supplements with synthetic phosphodiesterase type 5 inhibitors, J. Sex Med. 10(7), 1842-18492. 2. Low, M.Y., Zeng, Y., Li, L., Ge, X.W., Lee, R., et al. (2009) Safety and quality assessment of 175 illegal sexual enhancement products seized in red-light districts in Singapore, Drug Saf. 32, 1141-1146.

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