A Duluth company has agreed to stop making unproven medical claims about the amino acid dietary supplements it sells after the Food and Drug Administration filed for an injunction.

West Duluth Distribution Co., doing business as CHK Nutrition and NeuroResearch Clinics Inc., has been making drug-like claims that its amino acid capsules and powders can treat and cure various diseases, without the required regulatory approvals for a new drug, the Food and Drug Administration (FDA) said Wednesday.

The companies' owners, Martin C. Hinz of Florida and his daughter Amy Gunthert-Hinz of Duluth, signed a consent decree Tuesday agreeing to change their marketing tactics. There's been no accusations that anyone's been hurt by the products, said lawyer Mark DuVal, a regulatory expert the companies hired.

Their attorney Josiah Lamb said neither Hinz nor his daughter would comment. In a statement, CHK said its products are safe and effective.

"We have been in contact with representatives of the FDA, and we expect to resolve this matter shortly by making appropriate changes to our promotional materials and resume selling," it said.

Hinz could not immediately be reached for comment. DuVal described him as a well-known speaker and writer on the benefits of taking amino acid supplements. Hinz holds an active medical license in Minnesota, where he attended the University of Minnesota Medical School, according to the Minnesota Board of Medical Practice.

However, the board has taken several disciplinary actions against him, starting in 1996 when it suspended his license after he was hospitalized in Duluth for bipolar disorder with sleep deprivation. Later actions show continued concern over his ability to practice. It suspended his license again in 2001 after a skills audit "identified concerns with [his] medical knowledge, prescribing practices, competency, and recordkeeping," but stayed the suspension contingent on his full compliance with the terms, provisions and deadlines set by the board. The license was reinstated in 2005.

One of the things the FDA objected to was a link on CHK Nutrition's website to NeuroResearch Clinics' website where there were discussions about "amino-acid therapy" for treating such ailments as Parkinson's disease, Alzheimer's, depression and attention-deficit disorder. The FDA said it warned the company to stop making unapproved drug claims, but it didn't.

DuVal said he was sympathetic to the FDA's mission to stop "elixir salesmen." But he accused the agency of being overzealous in its attempts to regulate the ill-defined field of dietary supplements and probiotics, which includes encapsulated microorganisms such as those found in yogurt.

"It's a huge issue," DuVal said. "It's an emerging field, but it's an important one because that's where society is going. We're relying less on traditional Western medicine, which is reactive, and we're trying to be more proactive about our health."

CHK Nutrition is the latest Minnesota supplements company the FDA has hit.

In June, the FDA accused an Eden Prairie firm called UAS Laboratories of making unproven medical claims about its probiotic products, and U.S. marshals raided the company, seizing more than 80 cases of its products. In that case, the company also agreed to change its advertising, website and labels, said DuVal, who also represents that company.

The FDA sent both companies warning letters several years ago, which is how the agency has typically handled its disputes with the industry, DuVal said. Now the administration appears to be escalating its enforcement.

"Two in one year is pretty extraordinary," DuVal said.

The CHK products at issue are NeuroReplete, Neuro-R, Replete Extra, Neuro-RE, D5, Neuro-D, D5 Extra,Neuro-DE, D5 Mucuna, Neuro-M, 5-HTP, Neuro-5, Tyrosine Replete, Neuro-T, CysReplete and Neuro-C. They aren't sold in stores but by direct marketing and over the Internet.

Jennifer Bjorhus • 612-673-4683