Legal status · United States
Is Procyanidin C1 legal in the United States?
Written by Aaron CuhaReviewed Sep 2026
Direct answer
No. Procyanidin C1 is not an approved medicine in the United States; its classification is "Not approved; research use only". Nothing containing it is authorized for any use in people. Vials labeled "for research use only" are not exempt: that label does not make human use lawful. On the evidence, no human study is cited on its profile.
Procyanidin C1 in the United States at a glance
| Classification | Not approved; research use only |
|---|---|
| Note | Grape seed extracts containing procyanidins are sold as supplements; isolated procyanidin C1 is not a marketed product. |
| FDA approval status | Not approved for any indication. Not in clinical development. Present as one constituent of grape seed extracts sold as supplements; the isolated compound is a research chemical. |
| Human studies cited | 0 of 4 citations on the profile |
| Reviewed | Sep 2026 |
Classification and note come from the Procyanidin C1 profile, checked against U.S. Food and Drug Administration (FDA) listings at the reviewed date.
What this means
- 01
No product containing Procyanidin C1 is approved by FDA for any use in the United States, so nothing on the market is authorized for people.
- 02
"Research use only" is a vendor label, not a legal category that permits human use. It does not exempt a product from medicines law.
- 03
Importing, supplying or promoting it for human use can fall under medicines legislation in the United States. This page is general information, not legal advice.
What Procyanidin C1 is
A grape seed polyphenol reported in 2021 to kill senescent cells and extend lifespan in old mice. That paper has carried an Editorial Expression of Concern since March 2026, and there is no human evidence for the isolated compound.
Procyanidin C1 is a trimeric proanthocyanidin found in grape seed extract. The 2021 Nature Metabolism paper that put it on the map reported a concentration-dependent double action: at low concentrations it suppressed the senescence-associated secretory phenotype, and at higher concentrations it selectively killed senescent cells.
Mechanism: Reported in cultured cells and mice: at low concentrations procyanidin C1 suppresses senescence-associated secretory factors, acting as a senomorphic; at higher concentrations it induces apoptosis in senescent cells, acting as a senolytic. The concentration dependence is the central claim and it comes from the paper now under Editorial Expression of Concern.
Regulatory history: Not approved for any indication. Not in clinical development. Present as one constituent of grape seed extracts sold as supplements; the isolated compound is a research chemical.
How FDA treats this kind of product
Approves prescription drugs by indication and polices unapproved products, including peptides sold online. Compounding pharmacies may prepare some compounds under a prescription when the FDA places them on a permitted bulk-substances category.
The classification above is the The Longevity Archive reading of U.S. Food and Drug Administration listings for Procyanidin C1 at the reviewed date, not a legal opinion. Rules change, and importing, prescribing and possessing a compound can each be treated differently. Check the regulator directly before acting on anything here.
Procyanidin C1 in other countries
Frequently asked questions
Is Procyanidin C1 legal in the United States?
No. Procyanidin C1 is not an approved medicine in the United States; its classification is "Not approved; research use only". Nothing containing it is authorized for any use in people. Vials labeled "for research use only" are not exempt: that label does not make human use lawful. On the evidence, no human study is cited on its profile. Note: Grape seed extracts containing procyanidins are sold as supplements; isolated procyanidin C1 is not a marketed product.
Can I buy Procyanidin C1 in the United States?
No approved product exists to buy. In the United States Procyanidin C1 is classified as "Not approved; research use only", so there is no licensed pharmacy product. Vendors selling it "for research use only" are not selling it for human use, and that label does not change its legal status. This site does not list or recommend vendors. Note: Grape seed extracts containing procyanidins are sold as supplements; isolated procyanidin C1 is not a marketed product.
Is Procyanidin C1 FDA approved?
No. FDA status: Not approved for any indication. Not in clinical development. Present as one constituent of grape seed extracts sold as supplements; the isolated compound is a research chemical.. Current US classification: "Not approved; research use only". On the evidence, no human study is cited on its profile.
Related compounds in the United States
Full research profile
Mechanism, cited studies, FDA status and the full legal summary for Procyanidin C1 live on its compound profile.
Procyanidin C1 profileThis page is general information about the regulatory status of Procyanidin C1 in the United States, current as of Sep 2026. It is not legal advice, and classifications change; check U.S. Food and Drug Administration directly or consult a lawyer for a specific situation. Educational use only. This database summarizes published research. It is not medical advice and contains no dosing protocols or recommendations for personal use. The Longevity Archive has no vendor relationships and does not recommend where to buy anything.