The thiazolidinediones are the world's leading oral anti-diabetes drugs, and doctors regularly prescribe them as a 'last resort' drug when other medications have failed to reduce blood glucose levels.
Their heavy use is a puzzle, especially when you consider their safety record. Back in 2000, Rezulin (troglitazone), a thiazolidinedione developed by Warner Lambert, was withdrawn from the American market because it was found to cause liver toxicity. At the time, two of its rivals - Actos (pioglitazone) and Avandia (rosiglitazone) - were considered to be safer, and were allowed to stay on the market.
This may have been a mistake, judging by more recent safety reports. Just last month Avandia was found to dramatically increase the risk of bone fractures in women, and now researchers have discovered that Actos has exactly the same effect.
Apart from increasing the risk of fractures and liver toxicity, thiazolidinediones also cause edema, a condition that causes a swelling or fluid retention in the lungs, and they increase the risk of heart failure.
Despite these concerns, most of which have been known about for some time, doctors' prescribing of the drug family remains "robust", as one researcher puts it, which is more than can be said for the patient.
(Source: Journal of the American Medical Association, 2007; 297: 1645).
E-news broadcast 26 April 2007 No.354 [Subscribe]