Concerns have been raised after a diabetes drug that was urged to be withdrawn from sale more than two months ago remains available.
The Commission on Human Medicines advised an expert committee of the Medicines and Healthcare products Regulatory Agency (MHRA) in July that rosiglitazone, which is sold as Avandia, should be removed from sale.
The group raised concerns that taking the drug could increase the risk of suffering a heart attack.
In its report, the commission said the "risks of rosiglitazone outweigh its benefits".
And the group added that the drug no longer had a place in the UK market.
Now, the British Medical Journal (BMJ) has called for the drug to be removed immediately, and said it should never have been licensed.
Rosiglitazone, which is manufactured by GlaxoSmithKline (GSK), was approved by the European Medicines Agency (EMA) in 2000 to help lower blood sugar levels in patients with type 2 diabetes.
GSK said their "extensive research" showed the drug was "safe and effective when it is prescribed appropriately".
But since its approval several studies have suggested the drug may lead to a small overall increase in the risk of heart attacks and the BMJ's investigations editor, Dr Deborah Cohen, said the European approval process was not rigorous enough.
She also raised concerns about the quality of the data used by GSK, the lack of publicly available trial results for independent scientific scrutiny, and failures to act swiftly on emerging safety fears.
The journal said doctors were advising that no new patients should start taking the drug and patients already using rosiglitazone should review their options. Those at higher risk of heart disease should be advised to stop taking it.