The Ministry of Health has laid nine charges against the health supplement company Promisia Integrative.
It said the company's Arthrem joint support product was marketed as medicine, when it was not, which was a breach of the Medicines Act.
Promisia disputes all the charges and said it would "defend them vigorously" in a market announcement.
"Arthrem is not a medicine. It is a dietary supplement. Promisia has always ensured that its advertising is approved under the dietary supplement category," the company said.
Last year, MedSafe warned that Arthrem had been linked to harming liver functions among some people who had taken it and had adverse reactions.