A recent FDA recall should give every dietary supplement distributor reason to pause. Nalpac, a Michigan-based company, voluntarily recalled DTF Sexual Chocolate nationwide after the product was found to contain sildenafil and tadalafil — both prescription-only pharmaceutical compounds with real cardiovascular risks. The full recall notice is available on FDA's recall page.
The recall is the event. What I want to talk about is what comes before events like this — and why those things are almost always preventable.
Undeclared pharmaceuticals in supplement products are not a new problem. The FDA has identified this as one of its most persistent public health concerns, particularly in the sexual enhancement, weight loss, and bodybuilding categories. What is sometimes surprising to distributors and retailers is just how often the company triggering the recall is not the manufacturer — it is a downstream reseller who bought the product in good faith, had no idea what was in it, and is now holding the liability.
That is exactly the situation worth understanding.
Why Sildenafil and Tadalafil Keep Showing Up in Supplement Products
Sildenafil and tadalafil are the active pharmaceutical ingredients in Viagra and Cialis, respectively. They are PDE5 inhibitors — potent vasodilators that can cause serious cardiovascular events, particularly when combined with nitrate medications. They are legal only as prescription drugs in the United States, regulated under 21 CFR Part 314.
Their presence in a supplement product is not a labeling error. It is adulteration under 21 U.S.C. § 342(a)(2)(C), and it triggers mandatory recall authority under 21 CFR Part 7.
Here is what makes this category so persistently problematic: the consumer demand for "natural" sexual enhancement products is large, the supply chain is fragmented, and the economic incentive for unscrupulous manufacturers to spike products with pharmaceutical actives is real. A chocolate or gummy that actually "works" sells better than one that does not — and undeclared PDE5 inhibitors make products work in ways their ingredient labels cannot explain.
According to FDA data, the sexual enhancement category accounts for a disproportionate share of tainted supplement enforcement actions. Between 2007 and 2023, FDA identified over 950 products in this category containing undeclared pharmaceuticals or pharmaceutical analogs. That is not a small or obscure problem.
The lesson for distributors and retailers is uncomfortable but important: the product's packaging, marketing claims, and price point cannot tell you whether it is safe. Only testing can.
What Quality Systems Would Have Caught This
If you are a distributor — or a retailer, or a contract manufacturer — the Nalpac recall illustrates a gap that good quality systems are specifically designed to close. Here is what that looks like in practice.
Supplier Qualification and Incoming Material Controls
Under FDA's dietary supplement current Good Manufacturing Practices (21 CFR Part 111), manufacturers are required to establish specifications for each component and to verify that components meet those specifications before use (21 CFR § 111.70, § 111.75). Distributors who purchase finished products for resale are operating under a different model, but the underlying logic is the same: you are responsible for what you sell.
A robust supplier qualification program for finished dietary supplement products should include, at minimum:
- A current Certificate of Analysis (COA) for each lot, issued by the supplier
- Third-party lab verification of the COA — not just acceptance of the document itself
- A review of the supplier's quality system documentation, including their own 21 CFR Part 111 compliance status
- A formal supplier audit or, at minimum, a questionnaire-based assessment on a defined cycle
The COA alone is not enough. I have seen distributors accept a supplier-issued COA as a complete quality check. That is a gap. A COA tells you what the supplier says is in the product. A third-party test tells you what is actually there.
Identity and Adulteration Testing for High-Risk Categories
Sexual enhancement products, weight loss supplements, and bodybuilding products fall into what I consider a high-risk category for undeclared pharmaceuticals. For products in these categories, standard identity testing is not sufficient. You need targeted adulteration screening.
The analytical methods most commonly used for detecting undeclared PDE5 inhibitors include:
- High-Performance Liquid Chromatography (HPLC): Effective for quantifying known pharmaceutical actives
- Liquid Chromatography-Mass Spectrometry (LC-MS/MS): The gold standard for identifying both known adulterants and their structural analogs
- Nuclear Magnetic Resonance (NMR) Spectroscopy: Useful for broad-spectrum screening where the adulterant may not be a known compound
LC-MS/MS is the most important of these because manufacturers sometimes use sildenafil analogs — slightly modified molecules that are functionally similar but not listed in standard screening panels. A method that only checks for sildenafil itself may miss an analog that behaves like sildenafil in the body.
The cost of this testing is real. For a distributor sourcing a new product line, a comprehensive adulteration screen might run $400–$1,200 per test depending on the breadth of the panel and the laboratory used. That number looks different when you weigh it against the cost of a nationwide recall, the reputational damage, and the personal health risk to consumers.
Batch-Level Documentation and Lot Traceability
One of the things that slows recall response — and sometimes determines its scope — is traceability. When FDA requests distribution records under 21 CFR § 7.59, a company needs to be able to identify every lot it received, every customer it sold to, and the quantity involved. That is not a theoretical exercise.
A basic lot control system should capture:
| Record Element | What It Captures | Why It Matters in a Recall |
|---|---|---|
| Supplier lot number | Ties your inventory to the manufacturer's batch | Allows upstream investigation |
| Date of receipt | Establishes the intake window | Narrows scope of potential exposure |
| COA reference | Links the lot to quality documentation | Supports or challenges supplier accountability |
| Distribution records | Who received the product and when | Determines recall notification list |
| Quantity on hand vs. sold | Current inventory vs. what is in the field | Shapes the recall strategy |
Without these records, a recall becomes a guessing exercise. With them, it becomes a manageable, documented response.
The Regulatory Framework You Are Working In
It is worth being clear about the rules so there is no ambiguity about what FDA expects.
21 CFR Part 111 covers dietary supplement GMP requirements. It applies to manufacturers, packers, and holders of dietary supplements. If you are a distributor who repackages or relabels, you are operating as a manufacturer under this regulation and must maintain full GMP compliance.
21 CFR Part 7 governs recall procedures. Voluntary recalls — like Nalpac's — are encouraged by FDA, and companies that self-initiate recalls generally receive more cooperative treatment than those who resist. However, FDA also has mandatory recall authority under Section 423 of the FD&C Act for products that present a reasonable probability of serious adverse health consequences.
21 U.S.C. § 342(a) defines adulteration. A product containing an undeclared pharmaceutical active is adulterated by definition, regardless of whether the company knew it. Intent is not a defense against adulteration status.
21 CFR § 111.95 requires that you maintain records sufficient to demonstrate compliance. This includes supplier qualification records, COAs, testing results, and distribution records. These records must be kept for one year beyond the shelf life of the product, or two years after the date of manufacture if shelf life is not established.
For companies that market these products online, the FTC's substantiation requirements also come into play — but that is a separate conversation.
A Practical Compliance Framework for Distributors and Retailers
In my experience working with over 200 clients in the dietary supplement and consumer products space, the companies that avoid recalls share a few common habits. They are not complicated. They are just consistent.
1. Categorize your product portfolio by risk level. Sexual enhancement, weight loss, and sports performance products are high-risk. Treat them differently than a vitamin C capsule. Higher risk means more stringent supplier qualification, mandatory third-party testing, and shorter review cycles.
2. Never accept a COA as your final quality check. For any high-risk product category, require third-party lab confirmation before the product goes to sale. Build this cost into your sourcing model.
3. Build a supplier scorecard and use it. Track defect rates, COA accuracy (verified against your own testing), on-time delivery of quality documentation, and any prior regulatory history. Suppliers with FDA warning letters or prior recalls should face heightened scrutiny or be disqualified.
4. Establish a written quality agreement with every supplier. This document should define your testing expectations, acceptable quality levels, required documentation, and what happens in the event of a quality failure or recall. A quality agreement does not prevent a bad actor from adulterating a product, but it creates contractual accountability and clarifies responsibility.
5. Conduct a mock recall annually. Pick a random lot number and see how quickly and completely you can reconstruct the full distribution picture. If it takes more than a few hours or the picture is incomplete, your traceability system needs work.
6. Know your notification obligations. If you become aware that a product you distributed may be adulterated, you have an obligation to notify FDA and consider a recall. Waiting to see if the problem surfaces on its own is not a strategy. It is a liability.
The Difference Between a Distributor and a Manufacturer Under FDA Rules
This deserves its own section because I see the confusion regularly.
Many companies that purchase finished dietary supplement products and sell them under their own brand believe they are simply "distributors" and therefore not subject to manufacturing GMP requirements. This is often wrong.
Under 21 CFR § 111.3, the definition of "manufacturer" includes any person who packages or labels a dietary supplement. If you are putting your brand name on a product — even one you purchased as a finished good — you may be functioning as a manufacturer under FDA's framework. That means 21 CFR Part 111 applies to you. That means you are responsible for ensuring the product meets specifications. That means you cannot simply point to your supplier if the product is found to be adulterated.
This is not a technicality. It is the framework FDA actually enforces.
If you are unsure whether your operation triggers manufacturing GMP obligations, that is worth clarifying before your next product launch — not after a recall notice.
What This Means Right Now
The Nalpac recall is a useful reminder that undeclared pharmaceutical adulteration in supplements is not a historical problem that the industry has solved. It is an ongoing enforcement priority for FDA, and the companies most at risk are often the ones furthest from the manufacturing source — distributors and retailers who trusted their supply chain without verifying it.
The prevention framework is not complicated. Categorize risk honestly, test for what matters in your category, build traceability into your operations, and know what your regulatory obligations actually are — not what you assumed them to be.
In my view, the most expensive quality decision a supplement company can make is the one to skip testing because the product "comes from a reputable source." Reputable sources have bad days. Testing does not.
If you want to assess where your current quality system stands, explore our dietary supplement compliance consulting services at Certify Consulting or reach out directly to discuss your product portfolio.
For more on FDA enforcement patterns and how to build a compliant supplement operation, see our related resource on FDA warning letter trends in dietary supplements.
Last updated: 2026-04-21
Jared Clark
Principal Consultant, Certify Consulting
Jared Clark is the founder of Certify Consulting, helping organizations achieve and maintain compliance with international standards and regulatory requirements.