A "revolutionary" drug for treating congestive heart disease is a killer, its manufacturers, Boots, have admitted.
The drug, Manoplax, has been shown to increase the likelihood of death, when taken at the higher dosage of 100mg a day.
A preliminary study of 3500 patients taking 100mg of the drug shows they "have a significantly increased risk of death compared to those not receiving the drug," Boots admits.
The company maintains that no adverse effects have been seen in patients on the lower dosage of 75mg a day.
Manoplax was approved for British use in September and up to 40,000 people are estimated to be on the drug in Britain and the US.
Doctors are being advised to stop prescribing the higher dose.