Half Hill Farm Inc.
FDA issued a warning letter to Half Hill Farm Inc. (Woodbury, TN, United States) on Mar 6, 2026, citing 21 CFR 101.93 and 21 CFR 201.5. Subject: Unapproved New Drugs, Misbranded.
From the letter: “The claims on your website establish that the products are drugs under section 201(g)(1)(B) of the Act [21 U.S.C. 321(g)(1)(B)] because they are intended for use in the cure, mitigation, treatment, or prevention of disease.”
At a glance
What a reviewer notes before reading: findings, citations, the response deadline and what the letter warns of.
- Violations
- 4 findings · 3 issue types
- Cited
- 21 CFR 101.93, 21 CFR 201.5
- Response due
- 15 working days after receipt of this letter
- FDA asks for
- 1 actions
- Named as possible actions
- Seizure, injunction
- Issued by
- Human Foods Program
- Published status
- No close-out recorded
AI assisted findings
Model-assisted reading of each issue. Open one to see the FDA text it comes from, and check it against the full letter.
01Labeling, claims & marketing · 21 CFR 101.93(g)(2)(iv)(C)Website and labeling for mushroom extract products included disease claims, establishing intended use as drugs for treating or preventing diseases such as cancer and herpes simplex virus.
The claims on your website establish that the products are drugs under section 201(g)(1)(B) of the Act [21 U.S.C. 321(g)(1)(B)] because they are intended for use in the cure, mitigation, treatment, or prevention of disease.
02Design controlsProducts are new drugs without FDA approval because they are not generally recognized as safe and effective for the intended disease uses.
Your products are not generally recognized as safe and effective for the above referenced uses and, therefore, the products are “new drugs” under section 201(p) of the Act [21 U.S.C. 321(p)].
03Labeling, claims & marketingProducts are misbranded because they fail to bear adequate directions for layperson safe use, as the disease uses require practitioner supervision.
Accordingly, your Turkey Tail Mushroom Extract, Chaga Mushroom Extract, and Red Reishi Mushroom Extract products fail to bear adequate directions for their intended use and, therefore, the products are misbranded under section 502(f)(1) of the Act [21 U.S.C. 352(f)(1)].
04CAPAFDA deemed the firm's response to the Form FDA 483 inadequate, as it alleged labeling changes but provided no documentation.
In your response, you stated that you (b)(4). However, you did not provide documentation to support that those changes to the label have been made.
What FDA requested
- Respond in writing within 15 working days with the specific steps taken to address the violations, including an explanation of each step being taken to prevent recurrence, and copies of related documentation. If corrective actions cannot be completed within 15 working days, state the reason for the delay and the time within which you will do so. If you believe your products are not in violation of the Act, include your reasoning and any supporting information.
FDA Warning Letter
33 paragraphs · 3 sectionsText as published on FDA.gov, retrieved Sep 8, 2026. Layout added for reading; the wording is FDA’s. View on FDA.gov (opens in a new tab)
1Introduction
2 paragraphs
The U.S. Food and Drug Administration (FDA) conducted an inspection of your facility located at 110 W. High St., Woodbury, TN 37190 on 05/28/25 to 05/30/25. Based on inspectional findings and review of the product labeling collected during the inspection, as well as review of your website www.halfhillfarm.com, we have identified significant violations of the Federal Food, Drug, and Cosmetic Act (the Act) and applicable regulations. You can find the Act and FDA regulations through links on FDA's home page at www.fda.gov.
At the conclusion of the inspection on May 30, 2025, our investigator provided you with a Form FDA 483, Inspectional Observations (FDA 483). We acknowledge receipt of your response dated June 13, 2025, and we address your response below.
2Unapproved New Drugs
15 paragraphs
FDA reviewed your website at the Internet address www.halfhillfarm.com in February 2026 and has determined that you take orders there for the products Turkey Tail Mushroom Extract, Chaga Mushroom Extract, and Red Reishi Mushroom Extract. The claims on your website establish that the products are drugs under section 201(g)(1)(B) of the Act [21 U.S.C. 321(g)(1)(B)] because they are intended for use in the cure, mitigation, treatment, or prevention of disease. As explained further below, introducing or delivering these products for introduction into interstate commerce for such uses violates the Act.
Your website includes disease claims in the form of citations to publications or references. When scientific publications or references are used commercially by the seller of a product to promote the product to consumers, such references may become evidence of the product's intended use. For example, under 21 CFR 101.93(g)(2)(iv)(C), a citation of a publication or reference in the labeling of a product is considered to be a claim about disease treatment or prevention if the citation refers to a disease use and if, in the context of the labeling as a whole, the citation implies treatment or prevention of a disease. The following examples of citations on your website https://www.halfhillfarm.com/news-research/ used to market “Turkey Tail Mushroom Extract, Chaga Mushroom Extract, and Red Reishi Mushroom Extract” for disease treatment or prevention are evidence of your products’ intended use as drugs:
Under the Newspaper header:
“Farmers Turn To Cancer-Fighting – Cannon Courier – April 9, 2014”
Under the Research on Turkey Tail (Trametes Versicolor) mushrooms header:
“Turkey Tail mushrooms and our personal fight against cancer – Half Hill Farm – December 6, 2013”
“Complete clinical summary: Turkey Tail – Memorial Sloan Kettering Cancer Center.”
Under the “Research on Chaga (Inonotus obliquus) mushrooms” header:
“Ethanol extract of Innotus obliquus (Chaga mushroom) induces G1 cell cycle arrest in HT-29 human colon cancer cells – Nutrition Research and Practice – April 2015”
“Liquid extract from a Chaga medicinal mushroom, Inonotus obliquus (higher Basidiomycetes), prevents herpes simplex virus entry through inhibition of viral-induced membrane fusion – International Journal of Medicinal Mushrooms – 2013”
Under the “Research on Red Reishi (Ganoderma lucidum) mushrooms” header:
“Ganoderma lucidum (Reishi) in cancer treatment – NIH”
“Ganoderma lucidum exerts anti-tumor effects on ovarian cancer cells – International Journal of Oncology – May 2011”
“The Effect of Mushroom Beta-Glucans from Solid Culture of Ganoderma lucidum on Inhibition of the Primary Tumor Metastasis – Evidence-Based Complementary and Alternative Medicine – April 2014”
Your products are not generally recognized as safe and effective for the above referenced uses and, therefore, the products are “new drugs” under section 201(p) of the Act [21 U.S.C. 321(p)]. With certain exceptions not applicable here, new drugs may not be legally introduced or delivered for introduction into interstate commerce without prior approval from FDA, as described in sections 301(d) and 505(a) of the Act [21 U.S.C. 331(d), 355(a)]. FDA approves a new drug on the basis of scientific data and information demonstrating that the drug is safe and effective.
3Misbranded Drugs
8 paragraphs
A drug is misbranded under section 502(f)(1) of the Act [21 U.S.C. 352(f)(1)] if the drug fails to bear adequate directions for its intended use(s). “Adequate directions for use” means directions under which a layperson can use a drug safely and for the purposes for which it is intended (21 CFR 201.5). Prescription drugs, as defined in section 503(b)(1)(A) of the Act [21 U.S.C. 353(b)(1)(A)], can only be used safely at the direction, and under the supervision, of a licensed practitioner.
Your products Turkey Tail Mushroom Extract, Chaga Mushroom Extract, and Red Reishi Mushroom Extract are intended for treatment or prevention of one or more diseases that are not amenable to self-diagnosis, treatment, or prevention without the supervision of a licensed practitioner. Therefore, it is impossible to write adequate directions for a layperson to use your products safely for their intended purposes. Accordingly, your Turkey Tail Mushroom Extract, Chaga Mushroom Extract, and Red Reishi Mushroom Extract products fail to bear adequate directions for their intended use and, therefore, the products are misbranded under section 502(f)(1) of the Act [21 U.S.C. 352(f)(1)]. The introduction or delivery for introduction into interstate commerce of these misbranded drugs violates section 301(a) of the Act [21 U.S.C. 331(a)].
We also have the following comment:
We have reviewed your response to the FDA Form 483, dated June 13, 2025, and find it does not adequately address the violation. In your response, you stated that you (b)(4). However, you did not provide documentation to support that those changes to the label have been made.
This letter is not intended to be an all-inclusive statement of violations that may exist in connection with your products. 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.
Please notify FDA in writing, within 15 working days of receipt of this letter, of the specific steps you have taken to address any violations. Include an explanation of each step being taken to prevent the recurrence of violations, as well as copies of related documentation. If you cannot complete corrective actions within 15 working days, state the reason for the delay and the time within which you will do so. If you believe that your products are not in violation of the Act, include your reasoning and any supporting information for our consideration.
Your written reply should be directed to Natalie J. Reese, United States Food and Drug Administration, Human Foods Program, Office of Enforcement, 5001 Campus Drive, College Park, Maryland 20740-3835 or via email at HFP-OCE-DietarySupplements@fda.hhs.gov. Please reference CMS # 720213 on any submissions and within the subject line of any emails to us. If you have any questions, you may email at HFP-OCE-DietarySupplements@fda.hhs.gov.
Citations and trends
Each 21 CFR section, ISO 13485 clause and issue type in this letter, how often it appears across all letters, and its trend by the year FDA issued the letters. 2026 runs to Nov 3, 2026, compared with the same dates last year. Select a row or a bar to see those letters in Letters. As cited in this historical letter, not a statement of current requirements.
Regulations
Issue types
Record details
- Issuing center
- Human Foods Program
- Issuing office
- Human Foods Program
- Location
- Woodbury, TN, United States
- Letter posted date
- Apr 14, 2026
- Letter issue date
- Mar 6, 2026
- Addressed to
- Owner
- Inspection dates
- May 30, 2025
- Response window
- 15 working days after receipt of this letter
Read the source clause
Please notify FDA in writing, within 15 working days of receipt of this letter, of the specific steps you have taken to address any violations.
- Record length
- 1,157 words · 3 recorded redactions
- Published status
- No published close-out
- FDA reference
- 720213
- Original letter
- View on FDA.gov (opens in a new tab)
- Dataset last checked
- Nov 11, 2026 · How this is built
A response window is not a calculated due date. Source excerpts are selected passages. Finding interpretations and categories are model-assisted. Verify the original letter before relying on a finding.