TOKYO, Japan — A Japanese drugmaker whose dietary supplements are at the centre of a growing health scare reported on Thursday two more deaths potentially related to its tablets.

Last week, Kobayashi Pharmaceutical recalled three supplement brands — “Beni Koji Choleste Help” and two others — after customer complaints of kidney problems.

The over-the-counter products contain an ingredient called red yeast rice, or “beni koji”, which is supposed to help lower cholesterol.

Thursday’s announcement brings the total number of deaths under investigation by the company and health ministry to four, with more than 100 other people hospitalised.

Prime Minister Fumio Kishida said in parliament that “after the cause is identified, the government will examine what measures are necessary to prevent similar incidents”.

“We will clarify the causes and, if necessary, I think we need to consider all possible measures,” he said.

Kishida was responding to an opposition politician who had urged him to revise safety frameworks that were relaxed under former prime minister Shinzo Abe.

Kobayashi Pharmaceutical sells a wide range of health products marketed through television adverts in Japan.

Medical studies describe red yeast rice as an alternative to statins for lowering high cholesterol, but also warn of a risk of organ damage depending on its chemical make-up.

The Osaka-based company says it has also supplied red yeast rice to around 50 other firms in Japan and two in Taiwan.

“We were told yesterday by a bereaved family that a person who had been using Choleste Help had passed away due to kidney disease,” the drugmaker said in a statement.

It added it had been told separately that another person who had used Choleste Help in recent years had died.

“We are in the process of confirming the facts and causal relationships in both of these cases,” the statement said.

“However, we decided to make this report public from the viewpoint of prompt disclosure.”

The government has ordered several health-food makers to review their products, while informing foreign countries about the issue through Japan’s embassies, chief cabinet secretary Yoshimasa Hayashi said.

Dozens of Japanese firms that used beni koji provided by Kobayashi Pharmaceutical have separately announced recalls.

The affected products include health tablets as well as a rose-coloured sparkling sake, salad dressing, bread and miso paste used in many traditional dishes.

Kobayashi Pharmaceutical has said analysis had found a possibility that the products contained “ingredients we had not intended to include”.

But it said it did not find any citrinin produced by red yeast rice, which is toxic and can damage the kidneys.

A Kobayashi executive said last week that the company first received complaints about kidney problems in January.

“It is regrettable that Kobayashi Pharmaceutical did not provide information to the government while it was carrying out investigations to determine the cause,” Health Minister Keizo Takemi said on Tuesday.