Black box warning for Avandia

The Therapeutic Goods Administration (TGA) said it ordered the drug's manufacturer, GlaxoSmithKline, to introduce the warning on the product information leaflet ahead of the US food and Drug Administration, which stepped up its warnings yesterday.

The move follows two international studies earlier in the year that found Avandia significantly increased the risk of heart attack in some patients.

The new product warnings state that Avandia is "not recommended in patients with known ischaemic heart disease".

"Avandia has been shown to be associated with an increased risk of myocardial ischaemia (angina, infarction) in pooled short-term clinical studies, particularly in those who needed several anti-diabetic drugs or nitrates," it states.