What is an FDA Form 483?

A Form FDA 483 lists an FDA investigator’s written observations at the close of a facility inspection, issued under section 704(b) of the Federal Food, Drug, and Cosmetic Act. It documents conditions the investigator judged may violate FDA regulations. A 483 is not an enforcement action or a final determination that a violation occurred.

Does this Form 483 mean Mixlab WI LLC violated the law?

No. A Form 483 documents an investigator's observations only. FDA reviews the firm's written response and any corrective actions taken before deciding whether further action is warranted, and many 483s are closed without additional enforcement once a firm shows adequate correction.

What happens after a Form 483 is issued?

Argus HQ has recorded 2 total FDA actions tied to Mixlab WI LLC. The firm typically has 15 business days to submit a written response describing planned corrections; unresolved or serious findings can lead to a Warning Letter or other enforcement action.

Has Mixlab WI LLC had other FDA inspection citations?

Yes. Argus HQ has recorded 2 total FDA actions tied to Mixlab WI LLC, including 2 Form 483 inspection citations.

Form 483 Record: Mixlab WI LLC, May 1, 2026

Key facts

Firm	Mixlab WI LLC
FEI / inspection ID	3005946041
Inspection end date	May 1, 2026
Citation count	1

Key takeaway: FDA inspected Mixlab WI LLC in Wisconsin and issued a Form 483 listing 1 inspectional observation following an inspection that concluded 2026-05-01. FDA records classify Mixlab WI LLC as a producer of non sterile drug products. A Form 483 documents an investigator's findings at the close of an inspection under the Federal Food, Drug, and Cosmetic Act; it is not a final agency compliance determination. The observations on this page are drawn directly from the FDA-issued Form 483 record. A Form FDA 483 is issued at the close of an FDA facility inspection to list conditions an investigator observed that may violate the Federal Food, Drug, and Cosmetic Act or its implementing regulations. It reflects the investigator's professional judgment at that point in time and is not a final agency determination, an enforcement action, or proof that a violation occurred. Firms are expected to respond in writing, typically within 15 business days, describing the corrective and preventive actions they plan to take. FDA reviews that response, along with any follow-up evidence, before deciding what happens next. Many 483s are resolved through corrective action alone. When FDA judges a firm's response inadequate, or when the underlying conditions are serious enough, the observations documented here can lead to a Warning Letter or further regulatory action. This page presents the observations exactly as recorded on the FDA-issued document; always confirm citation language against the original record before relying on it.

Citations explained

Observation 1 — { ~r""- ... \..,..,-::i._~ U.S. FOOD & DRUG ADMINISTRATION Ii - May 1, 2026 Mixlab WI LLC

{ ~r""- ... \..,..,-::i._~ U.S. FOOD & DRUG ADMINISTRATION Ii - May 1, 2026 Mixlab WI LLC Attention: Ms. Valerie Klippel Pharmacist-In-Charge 407 West Silver Spring Drive Milwaukee, WI 53217 (b) (6), (b) (7)(C) Re: Case 729008 Dear Ms. Klippel: The U.S. Food and Drug Administration (FDA) inspected your facility, Mixlab WI LLC, 407 West Silver Spring Drive, Milwaukee, WI 53217, from July 14 through July 24, 2025. During the inspection, the inspection team noted deficiencies in your practices for producing animal drugs and issued Form FDA 483. The inspection team also discussed the circumstances under which you produce animal drugs from bulk drug substances and distribute them, including copies of FDA-approved products. You responded to the inspection in writing on August 13, 2025, September 12, 2025, and September 19, 2025. We have reviewed your responses and discuss them in the relevant parts of this letter. For the reasons set forth below, you produce and distribute adulterated and misbranded animal drugs in violation of sections 301(a) and 301(k) of the Federal Food, Drug, and Cosmetic Act (FD&C Act). A. Unapproved New Animal Drugs You compound drugs for animals from bulk drug su A Form FDA 483 is issued at the close of an FDA facility inspection to list conditions an investigator observed that may violate the Federal Food, Drug, and Cosmetic Act or its implementing regulations. It reflects the investigator's professional judgment at that point in time and is not a final agency determination, an enforcement action, or proof that a violation occurred. Firms are expected to respond in writing, typically within 15 business days, describing the corrective and preventive actions they plan to take. FDA reviews that response, along with any follow-up evidence, before deciding what happens next. Many 483s are resolved through corrective action alone. When FDA judges a firm's response inadequate, or when the underlying conditions are serious enough, the observations documented here can lead to a Warning Letter or further regulatory action. This page presents the observations exactly as recorded on the FDA-issued document; always confirm citation language against the original record before relying on it.

What a Form 483 means

A Form FDA 483 is issued at the close of an FDA facility inspection to list conditions an investigator observed that may violate the Federal Food, Drug, and Cosmetic Act or its implementing regulations. It reflects the investigator's professional judgment at that point in time and is not a final agency determination, an enforcement action, or proof that a violation occurred. Firms are expected to respond in writing, typically within 15 business days, describing the corrective and preventive actions they plan to take. FDA reviews that response, along with any follow-up evidence, before deciding what happens next. Many 483s are resolved through corrective action alone. When FDA judges a firm's response inadequate, or when the underlying conditions are serious enough, the observations documented here can lead to a Warning Letter or further regulatory action. This page presents the observations exactly as recorded on the FDA-issued document; always confirm citation language against the original record before relying on it.

Mixlab WI LLC’s FDA history

Argus HQ has recorded 2 total FDA actions tied to Mixlab WI LLC: 0 warning letters, 0 recalls, 0 approval records, and 2 Form 483 inspection citations.

Frequently asked questions

What is an FDA Form 483?: A Form FDA 483 lists an FDA investigator’s written observations at the close of a facility inspection, issued under section 704(b) of the Federal Food, Drug, and Cosmetic Act. It documents conditions the investigator judged may violate FDA regulations. A 483 is not an enforcement action or a final determination that a violation occurred.
Does this Form 483 mean Mixlab WI LLC violated the law?: No. A Form 483 documents an investigator's observations only. FDA reviews the firm's written response and any corrective actions taken before deciding whether further action is warranted, and many 483s are closed without additional enforcement once a firm shows adequate correction.
What happens after a Form 483 is issued?: Argus HQ has recorded 2 total FDA actions tied to Mixlab WI LLC. The firm typically has 15 business days to submit a written response describing planned corrections; unresolved or serious findings can lead to a Warning Letter or other enforcement action.
Has Mixlab WI LLC had other FDA inspection citations?: Yes. Argus HQ has recorded 2 total FDA actions tied to Mixlab WI LLC, including 2 Form 483 inspection citations.

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Full FDA history for Mixlab WI LLC

Compiled by Argus HQ Research from FDA primary sources · Reviewed by Andy Gaber, Founder

Cite this record

Reusing this data in reporting or research? Here’s a ready-made citation.

APA

Argus HQ Research (2026). Form 483 Record: Mixlab WI LLC, May 1, 2026 — 1 Citations. Digital Empire Holdings LLC. Retrieved from https://argushq.ai/483/mixlab-wi-3005946041-2026-05-01

MLA

"Form 483 Record: Mixlab WI LLC, May 1, 2026 — 1 Citations." Argus HQ Research, Digital Empire Holdings LLC, 2026, argushq.ai/483/mixlab-wi-3005946041-2026-05-01.

Chicago

Argus HQ Research. "Form 483 Record: Mixlab WI LLC, May 1, 2026 — 1 Citations." Digital Empire Holdings LLC. Accessed July 29, 2026. https://argushq.ai/483/mixlab-wi-3005946041-2026-05-01.

BibTeX

@misc{argushq_argushq_ai_483_mixlab_wi_3005946041_2026_05_01_2026,
  title = {Form 483 Record: Mixlab WI LLC, May 1, 2026 — 1 Citations},
  author = {{Argus HQ Research}},
  year = {2026},
  publisher = {Digital Empire Holdings LLC},
  url = {https://argushq.ai/483/mixlab-wi-3005946041-2026-05-01},
  note = {Accessed: July 29, 2026}
}

Source: FDA.gov — Inspection Classification Database ↗