The trouble is that anyone can create a health-related website

Dr Paul Lambden

However, the survey found that few patients were willing to use the 20,000 health-related websites that could share the load.

The internet provides instant information, allows almost total anonymity and operates at hours to suit the patient, but five times as many people turn to untrained friends relatives or colleagues than go online, the survey found.

In attempt to persuade more people to make use of the net, The Stationery Office has published a guide to internet health sites, Your Health and the Internet.

Click here to read about the health sites recommended in the guide

No restrictions

Dr Paul Lambden, co-author of the guide and previously an adviser to the Parliamentary Health Select Committee, said: "The trouble is that anyone can create a health-related website. There are no restrictions or governing bodies.

"Doctors from sites based abroad are not registered with the UK's General Medical Council and some products or drugs that can be bought online are illegal in the UK.

"People can be emotional or distressed when they or a loved one are unwell, and some websites provide ill-informed advice at this difficult time."

The hazards of relying on the web for advice were graphically illustrated by the case of a man who refused traditional cancer treatment in favour of an alternative remedy offered on the internet.

He died after taking hydrazine sulphate, a substance used in rocket fuel.

Despite this Dr Lambden says the internet contains a host of useful health-related material, from online medical advice and drug purchasing to teenage pregnancy news groups and information on drug and alcohol addiction.

Dr Lambden said: "Your Health and The Internet is a guide to the best the Net has to offer.

"By telling consumers what to trust and what to ignore, we hope it will begin to turn the internet into a viable alternative to the already overburdened NHS."