The British Medical Association (BMA) has called for a ban on doctors prescribing drugs over the internet.

The call is in response to a private doctor from south London who has set up a medical practice via the internet and is offering consultations via the web.

Click here to read about the internet prescribing scheme

The BMA is concerned that doctors cannot ascertain sufficient detail about a patient's condition simply by an exchange of email.

It is also concerned that patients may use the web to obtain drugs they do not need.

Dr Paul Cundy, a member of its IT committee, said people who sought advice from these doctors were "at the mercy of the internet".

When it comes to online consultation or diagnosis, then I think the internet is simply not robust enough

Dr Paul Cundy, BMA

"There are no regulations to protect patients and they are completely and utterly at the mercy of internet doctors," he said.

There are an estimated 20,000 sites on the Internet offering information about health and an increasing number are offering advice directly to individual patients.

In February, Dr Julian Eden a GP in London launched what is thought to be the first website in the UK to offer diagnoses and prescriptions to patients over the internet.

Already 600 patients have signed up to his service.

Dr Eden believes the service is a safe alternative to face-to-face consultations with GPs.

Regulations

However, the BMA believes that the government should be doing more and that the lack of regulations in this area could put patients at risk.

Dr Cundy said patients could find they are being treated by bogus doctors with little or no qualifications.

Dr Laurence Buckman says an internet consultation is not sufficient

Patients are normally protected from bogus doctors because all doctors must be registered with the General Medical Council (GMC) before they are allowed to practice.

However, Dr Cundy said checking if an internet doctor is registered does not offer 100% protection to patients.

"There is no way of telling if a doctor working on the internet is who he says he is.

"The doctor might give his name as someone who is registered with the GMC but really it is impossible to tell.

"The only way to actually know if the person you are dealing with is who they say they are is to physically exchange their signature and to use encryption for any email consultations."

He added: "If a patient is simply seeking information about a certain condition then the internet has tremendous potential.

"But when it comes to online consultation or diagnosis, then I think the internet is simply not robust enough."

The Patients Association has also warned people against using internet treatment services.

You can easily miss something quite dangerous

Dr Laurence Buckman, BMA

Dr Laurence Buckman, a senior member of the BMA's GP committee, said: "You can easily miss something quite dangerous.

"Somebody who is coughing may have TB, they may have lung cancer, they may just have a cold, but all of them will say 'I have a cough doctor'.

"You will not know what the matter is until you ask a few more questions, and asking questions over the internet is exactly the same as writing them a letter - you would not a write a letter to somebody and say, 'tell me about your cough'."

Mike Stone, its director, said face to face contact between GPs was important.

He also called for regulation of medical sites.

"We would like to see some sort of kite mark to say the site is a good site, that it is acceptable to professional bodies and patient organisations and that it is offering credible advice.

"You can't police the internet but if there was some sort of kite mark then people could see that it is a valid site."