Denmark is investigating potential links between glucosamine use and elevated cholesterol levels. Possible heart and lung clotting side effects are also being assessed. The Danish Medicines Agency (DMA) called for input from companies marketing glucosamine in Denmark, where it is sold as an over-the-counter drug, as well as medicines agencies and glucosamine supplement manufacturers in other European member states.
Heading the investigation, DMA chief medical officer Doris Stenver was due to deliver her report to the European Union body, the European Medicines Agency, as FF&N went to press.
The DMA stated there was no action planned in the meantime and asserted that it was an investigation, not a trial. ?It is important to examine whether there is a connection between treatment with glucosamine and increased cholesterol count. So far, it is only a suspicion, and there might be other explanations for the increase in cholesterol count.? Swedish medical authorities were also conducting inquiries.
The Danish probe was sparked by a doctor who reported high cholesterol in three female patients who had been prescribed glucosamine supplements for joint problems.
About 10 Danish supplements companies submitted comments on adverse event reports and clinical trial data. ?The number of people taking glucosamine during the period in which the three women took glucosamine is not known exactly, but it is in excess of 100,000,? Danish supplements company Pharma Nord said in its DMA submission. ?At least 13 randomised, double-blind trials of glucosamine for osteoarthritis have been made to date. None indicated that glucosamine may have an adverse effect on blood lipids,? said Pharma Nord?s pharmacovigilance manager, Douglas Hunter. ?The medical literature does not appear to contain any case reports indicating an adverse effect of glucosamine on blood lipids despite 20 years? use of glucosamine, including its use in large markets such as the US and UK.? He added: ?While the possibility of an adverse effect of glucosamine on blood lipids in certain individuals cannot be entirely excluded, the available information does not suggest that therapeutic doses of glucosamine have an adverse effect on lipid metabolism.?
UK supplement manufacturer and retailer Holland & Barrett said it had no data suggesting a link between glucosamine use and elevated cholesterol or heart and lung clotting. Its regulatory affairs manager, Sharon Morey, said Holland & Barrett glucosamine supplements (classified as foods in the UK) carried label advice cautioning those with diabetes and shellfish allergies to withhold consumption.
?Even if there were found to be a link, each batch needs to be assessed because not all glucosamine is the same,? she said.
San Diego-based Nutrition Business Journal estimates the worldwide glucosamine market at more than $1.5 billion.
Glucosamine and other joint health supplements such as chondroiton received a boost recently when pharma giant Merck withdrew its $2.5 billion arthritis drug Vioxx after it was found to increase the likelihood of heart attack and stroke.