Doctors have been banned from wearing ties in an effort to contain the spread of superbug MRSA.
An NHS trust has told hospital staff, including senior consultants, that the wearing of ties and "other superfluous clothing" could result in disciplinary action.
The rules have been introduced by the Brighton and Sussex University Hospitals NHS Trust in a bid to reduce its rate of MRSA infection, which is one of the highest in England.
The new dress code policy also bans staff involved in direct clinical care from wearing jewellery, watches, scarves and wraps.
But doctors say the new rules stem from political correctness rather than scientific evidence and fear that patients will have less confidence in casually dressed medics.
One consultant, who works for the trust but did not want to be named, told the Sunday Times: "If you come to see a consultant, you will be greeted by an open-neckshirted doctor who will look as if he is the hospital DJ, but will in fact be the consultant."
Dr Michael Dixon, chairman of the NHS Alliance, which represents primary care trusts, and wears a bow-tie at his GP surgery, said: "This is political correctness rather than science. Patients need to be able to respect and trust their doctors and going around without ties might damage that relationship."
Earlier this year the British Medical Association suggested that doing away with functionless items of clothing such as ties may help reduce rates of MRSA and other hospital acquired infections.
More than 3,500 cases of MRSA blood-stream infection were reported in NHS hospitals between October 2005 and March 2006 and the number of deaths where the superbug is mentioned on death certificates has increased each year from 1993 to 2004.
A spokeswoman for the trust said action was needed to improve infection control rates and that the new measures were introduced following consultation with staff.
Matthew Fletcher, medical director for the trust, said: "Reducing our MRSA rates is at the top of this trust's list of priorities and the new dress code policy is a part of a broad infection control strategy. The policy is about doing everything to minimise the risk of infections spreading.
"This includes removing clothing which prevents staff from washing their hands effectively. All staff, both male and female, involved in direct clinical care will be expected to not wear jewellery, watches, ties, scarves, wraps and other superfluous clothing.
"We do know that this will involve a culture change because many doctors are used to wearing a jacket and tie, particularly when delivering bad news, and many patients expect doctors to look 'smart'.
"But the simple fact is reducing the spread infection is more important than looking smart and both doctors and patients need to accept that ties are not essential for the delivery of a professional service and good healthcare."