Up to 800 asthma patients die needlessly every year because doctors prescribe the wrong medication or fail to monitor them properly.
Prescription errors are a factor in nearly half of the deaths, according to a study by doctors.
Other patients have not been offered check-ups or advice on how to avoid attacks. Around 1,250 Britons die from asthma every year. The mortality rate is the third highest in Europe, behind only Estonia and Spain.
And the latest figures show that the numbers have been steadily rising since 2009 when there were 1,140 deaths.
In the largest study of its kind, the Royal College of Physicians closely examined the deaths of 195 Britons from asthma in 2012 and 2013, including 28 children.
They found prescription errors had occurred in 47 per cent of cases, with GPs giving patients only short-term relieving inhalers rather than preventative medication that stops them having an attack.
A further 10 per cent had been treated in hospital for asthma a month before they died but had been discharged without the correct medication and not been properly monitored since.
More than a fifth had gone to A&E suffering an asthma attack at least once in the year before they died, including 11 per cent who had been admitted twice or more.
Care was particularly poor for children. The report concluded that in 26 out of the 28 child deaths there were ‘potentially avoidable factors’. Overall, it found that 130 of the 195 deaths — 67 per cent — could have been prevented.
The authors say these figures are consistent with previous, smaller studies into avoidable asthma deaths.
If this is true across the UK, then around 800 of the 1,250 deaths which occurred in 2012 could have been prevented.
Kay Boycott, chief executive of the charity Asthma UK, said the research ‘has identified prescribing errors of a frankly horrifying scale and is a damning indictment of current routine practice’.
She added: ‘In many of these cases the warning signs were ignored.’ Dr Kevin Stewart, clinical director at the RCP, said: ‘It’s time to end our complacency about asthma, which can, and does, kill, Daily Mail informs.