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Distributor RFR, LLC MARCS-CMS 643724 —

Delivery Method:
VIA Electronic Mail

Recipient Name
Mr. Roger L. Flores
Recipient Title
Owner and Manager
Distributor RFR, LLC

3580 NW 85th Ct Apt 150
Doral, FL 33122-1986
United States

Issuing Office:
Center for Drug Evaluation and Research | CDER

United States


January 9, 2023

RE: 643724

Dear Mr. Flores:

The U.S. Food and Drug Administration (FDA) inspected your facility located in Doral, FL, on June 2-3, 7, 10, and 14, 2022. FDA obtained a sample and labeling of your product “SANGTER Natural Male Energy Supplement” (hereinafter “SANGTER Energy Supplement”) during the inspection. We also reviewed your firm’s website at www.sangter.com.

Based on the inspection and review of your product labeling, including your firm’s website, FDA determined that “SANGTER Energy Supplement” is an unapproved new drug sold in violation of sections 505(a) and 301(d) of the Federal Food, Drug, and Cosmetic Act (FD&C Act), 21 U.S.C. 355(a) and 331(d). Furthermore, the product is a misbranded drug under section 502 of the FD&C Act, 21 U.S.C. 352, and sold in violation of section 301(a) of the FD&C Act, 21 U.S.C. 331(a). As explained further below, introducing or delivering this product for introduction into interstate commerce violates the FD&C Act.

FDA confirmed through laboratory analysis that a sample of your product, “SANGTER Energy Supplement,” contains the undeclared active pharmaceutical ingredient (API), sildenafil, which is a phosphodiesterase type-5 (PDE-5) inhibitor. Sildenafil is the active pharmaceutical ingredient in Viagra, an FDA-approved prescription drug used to treat erectile dysfunction (ED).1

Information on the labels and/or labeling of “SANGTER Energy Supplement” demonstrates that the sampled product is marketed as a dietary supplement. However, under section 201(ff)(3)(B)(i) of the FD&C Act, 21 U.S.C. 321(ff)(3)(B)(i), a dietary supplement may not include an article that is approved as a new drug under section 505 of the FD&C Act unless that article was marketed as a dietary supplement or food before its approval as a drug. FDA approved Viagra (containing sildenafil as the active ingredient) as a new drug on March 27, 1998. Prior to that date, sildenafil had not been marketed as a food or dietary supplement. Given that sildenafil was not marketed as a dietary supplement or as a food before Viagra was approved, “SANGTER Energy Supplement” is excluded from the definition of a dietary supplement under section 201(ff)(3)(B)(i) of the FD&C Act, 21 U.S.C. 321(ff)(3)(B)(i).

Unapproved New Drug

“SANGTER Energy Supplement” is a drug as defined by section 201(g)(1) of the FD&C Act, 21 U.S.C. 321(g)(1) because it is intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease and/or intended to affect the structure or any function of the body.

Examples of claims observed on your website homepage, www.sangter.com, that establish the intended use of this product as a drug include, but may not be limited to, the following:

• “100% Natural Male Performance Booster”
• “Damiana (turnera diffusa) It is a plant known for its aphrodisiac qualities that help stimulate the sexual appetite or libido”
• “In just 30 minutes or less after consumption you will feel its effect, more energy, more sexual desire and more power.”
• “Its main use applies to erectile dysfunction and low sexual desire, but it is also used against general weakness, painfulness, spontaneous sweat.”

“SANGTER Energy Supplement” is not generally recognized as safe and effective for its above referenced uses and, therefore, is a “new drug” under section 201(p) of the FD&C Act, 21 U.S.C. 321(p). With certain exceptions not applicable here, a new drug may not be legally introduced or delivered for introduction into interstate commerce without prior approval from the FDA, as described in sections 301(d) and 505(a) of the FD&C Act, 21 U.S.C. 331(d) and 355(a). There is no FDA-approved application in effect for “SANGTER Energy Supplement.” Introduction or delivery of this product into interstate commerce without an approved application violates sections 505(a) and 301(d) of the FD&C Act, 21 U.S.C. 355(a) and 331(d).

Misbranded Drug

“SANGTER Energy Supplement” is also misbranded under section 502(f)(1) of the FD&C Act, 21 U.S.C. 352(f)(1), in that the labeling fails to bear adequate directions for its intended use(s). “Adequate directions for use” means directions under which a layman can use a drug safely and for the purposes for which it is intended, 21 C.F.R. 201.5. All PDE-5 inhibitors which have been approved for marketing by FDA are limited by an approved new drug application to use under the supervision of a practitioner licensed by law to administer such drugs. Prescription drugs can only be used safely at the direction and under the supervision of a licensed practitioner. “SANGTER Energy Supplement,” which contains undeclared sildenafil, is also a prescription drug as defined in section 503(b)(1)(A) of the FD&C Act, 21 U.S.C. 353(b)(1)(A), in light of its toxicity or potential for harmful effects, methods of use, or collateral measures necessary for its use. Therefore, it is impossible to write “adequate directions for use” for prescription drugs, including “SANGTER Energy Supplement.” “SANGTER Energy Supplement” is not exempt from the requirements that its labeling bear adequate directions for use by a layperson, 21 CFR 201.100(c)(2) and 201.115, because there is no FDA-approved application in effect for this product. For these reasons, “SANGTER Energy Supplement” is misbranded under section 502(f)(1) of the FD&C Act.

Additionally, “SANGTER Energy Supplement” is misbranded under section 502(a) of the FD&C Act, 21 U.S.C. 352(a). Under section 502(a) of the FD&C Act, 21 U.S.C. 352(a), a drug is misbranded if its labeling is false or misleading in any particular. Section 201(n) of the FD&C Act, 21 U.S.C. 321(n), provides that, in determining whether an article's labeling or advertising “is misleading there shall be taken into account . . . not only representations made or suggested . . . but also the extent to which the labeling or advertising fails to reveal facts material in light of such representations.” The labeling for “SANGTER Energy Supplement” does not declare that the product contains a PDE-5 inhibitor. The use of PDE-5 inhibitors can be associated with significant safety issues and the risk of serious adverse events. The undeclared PDE-5 inhibitors in “SANGTER Energy Supplement” may pose serious health risks because consumers with underlying medical issues may take the products without knowing that they can cause serious harm or interact in dangerous ways with other drugs they may be taking. For example, PDE-5 inhibitors may interact with nitrates found in some prescription drugs (such as nitroglycerin) and can lower blood pressure to dangerous levels. Consumers with diabetes, high blood pressure, or heart disease often take nitrates. The failure to disclose this ingredient in the product’s labeling renders “SANGTER Energy Supplement” misbranded under section 502(a) of the FD&C Act.

The undeclared sildenafil in “SANGTER Energy Supplement” also causes the product to be misbranded under section 502(f)(2) of the FD&C Act, 21 U.S.C. 352(f)(2), because the labeling lacks adequate warning for the protection of users. As previously noted, there is a potential for serious health risks associated with this product, particularly since anyone who takes these products would be unaware of the presence of the undeclared drug ingredient and placed at risk for the associated adverse events.

The introduction, delivery for introduction, or causing the introduction or delivery for introduction into interstate commerce of this misbranded drug is a prohibited act under section 301(a) of the FD&C Act, 21 U.S.C. 331(a).


This letter is not intended to be an all-inclusive statement of violations that may exist in connection with your product. You are responsible for investigating and determining the causes of any violations and for preventing their recurrence or the occurrence of other violations. It is your responsibility to ensure that your firm complies with all requirements of federal law, including FDA regulations.

This letter notifies you of our concerns and provides you an opportunity to address them. Failure to adequately address this matter may result in legal action including, without limitation, seizure and injunction.

FDA acknowledges that on August 1, 2022, you initiated a voluntary nationwide recall of Lot #48656, Exp. 01/2025 of “SANGTER Energy Supplement,” 3000 mg, packaged in 7-count blister packs within a carton to the consumer level. We also acknowledge that you notified your customers of the recall by press release on August 2, 2022.

Please notify FDA in writing, within fifteen working days of receipt of this letter, of the specific steps you have taken to correct these violations. Include an explanation of each step being taken to prevent the recurrence of violations as well as copies of related documentation. If you believe that your products are not in violation of the FD&C Act, include your reasoning and any supporting information for our consideration. If you cannot complete corrective action within fifteen working days, state the reason for the delay and the time within which you will complete the correction.

Your response should be sent to U.S. Food and Drug Administration, Center for Drug Evaluation and Research/Office of Compliance/Office of Unapproved Drugs and Labeling Compliance by e-mail to FDAADVISORY@fda.hhs.gov.


CAPT Tina Smith
Acting Director
Office of Unapproved Drugs and Labeling Compliance
Center for Drug Evaluation and Research
Food and Drug Administration


1 FDA has issued a warning to consumers not to use “SANGTER Energy Supplement.” U.S. Food & Drug Administration, Public Notification: Sangter Natural Male Energy Supplement contains hidden drug ingredient, (November 10, 2022), https://www.fda.gov/drugs/medication-health-fraud/public-notification-sangter-natural-male-energy-supplement-contains-hidden-drug-ingredient.

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