Elan Pharmaceuticals has been reprimanded by the US Food and Drug Administration (FDA) over conditions at one of its seven plants in the United States.

The US regulator found the company, based in Athlone, Co Westmeath, had not conducted adequate testing or validation on one of its blood pressure products before releasing it on the market. It also found that laboratory analytical equipment at the Gainsville, Georgia plant of its wholly-owned subsidiary Elan Holdings had not been maintained in good repair, nor had sufficient records of test results been kept.

The plant produces Verelan and Verelan PM, which are used in the treatment of high blood pressure. Sales of the affected products amount to $12 million (€12.8 million), less than 0.5 per cent of annual group sales.

The FDA said the violations were not known to have caused any immediate risk to public health.

Elan has signed a "consent decree of permanent injunction", committing it to meeting certain standards at the plant in the future and agreeing to annual inspections at its own cost for the next three years.

An FDA spokesman said that while such consent decrees were not unprecedented, they were fairly unusual. It is the first time Elan has received such a censure.

A company spokesman said it had upgraded the plant and was now in compliance with FDA regulations. He pointed out that the FDA had imposed no fine on the company or insisted on a product recall or interruption of production, as it had the right to do under such decrees.

"Patients who depend on Verelan and Verelan PM should rest assured that their current supply is both safe and effective," said the spokesman. "Our commitment to improving patient lives remains undiminished."