Thousands of Irish people taking the drug Vioxx have been told to seek medical advice, after the company which makes it admitted yesterday that it increased the risk of heart attack and stroke.
Merck & Co withdrew the drug from circulation worldwide after clinical trials showed the heightened risks. The company's share price fell dramatically as a result.
Those taking the drug, which is widely used to treat the pain associated with arthritis, were advised last night by the Irish Medicines Board (IMB) to contact their doctors or pharmacists about discontinuing the treatment and discussing options for alternative medication.
The IMB said it would be immediately notifying doctors and hospitals that the drug was being recalled.
The drug has been licensed in the Republic since 1999 and to date the IMB said it has received just eight reports of "cardiovascular type adverse effects" associated with it. These were not deaths, a spokeswoman stressed.
Merck decided to pull Vioxx off the market yesterday after a three-year trial in the US showed that use of it beyond 18 months increased the risk of cardiovascular events, including heart attack and stroke, by between 300 and 400 per cent. The trial, involving 2,600 people, was attempting to show whether the drug could reduce the risk of colon cancers. It has now been suspended.
The product generated $2.5 billion (approximately €2 billion) in sales for Merck last year.
It is not known how many Irish people are taking the drug. However, figures provided by the General Medical Services (Payments) Board show it was prescribed 117,428 times to medical-card patients alone in 2003. Some of these would be repeat prescriptions.
Dr Paul O'Connell, president of the Irish Society for Rheumatology, said last night the withdrawal of the drug was unexpected.
He said Vioxx was a widely used anti-inflammatory in this country. It is usually prescribed for short-term use, he said, but many people with chronic arthritis would be prescribed it for long-term use. It is a once-daily medication.
Furthermore, Dr O'Connell said that for many people taking it their arthritis was not a very serious condition so he advised them to stop taking the drug if they were able to, take paracetamol instead for pain and seek medical advice over the next few days if they need to.
"For somebody who has already stopped taking it, as far as we know, there is no worry so they do not need to seek medical advice."
Asked if a patient who stops taking the drug should be worried about the effect it has had on them, he said the nature of the drug was "such that it would be out of the system within a number of days of stopping and after that time it's assumed there is no additional risk".
Merck & Co is the parent company of Merck Sharp & Dohme Ireland (Human Health) Ltd which employs 570 people in Dublin and Co Tipperary. Vioxx is not manufactured in Ireland and a spokeswoman for the Irish operation said the company did not foresee the withdrawal of the drug as having an impact on jobs in the Republic.
A Dublin-born researcher was the first to identify a connection between drugs like Vioxx and cardiovascular problems. Prof Garret FitzGerald, University of Pennsylvania, has researched the action of these drugs, known as Cox-2 inhibitors, for some years. He yesterday welcomed Merck's decision to withdraw the product.