How the internet ruined my health - confessions of a cyberchondriac

'It started two years ago when I started seeing white flecks out of my left eye and I checked on the internet to find out what was wrong," says Fiona, a 30-year-old sales executive from Derry in Northern Ireland. "One site said it might be a form of cancer so I booked myself in straight away to see my GP. He said nothing was wrong and that they would disappear of their own accord."

A happy ending you might think, but no. "I began to notice other things wrong with me after that," says Fiona. "I was excessively tired and thought I had an irregular heartbeat. I kept looking up the symptoms on the internet and going back to my GP, who kept insisting I was more healthy than most people."

Fiona joined online self-help groups, signed up for medical newsletters and emailed specialists around the world. As one of a growing number of people who experts believe are diagnosing illnesses at the click of a mouse, she became part of an emerging breed of hi-tech hypochondriacs - the cyberchondriacs.

Surveys show that while around a third of patients visiting GPs turn out to have nothing physically wrong with them, 5 per cent have actually convinced themselves they are suffering from a conditions they don't have. This "health anxiety" (the modern term for hypochondria) is fuelled by the huge amount of medical information we have at our fingertips. Cyberchondria is a particularly virile strain of this illness-paranoia and the direct result of the proliferation of websites devoted to health. Over the course of six months, Fiona reckons she visited her local 10 times with different "illnesses". "In the end my GP told me I had a panic disorder and that placated me," she says. But it hasn't quelled her appetite for health websites. These days, though, she confines her searches to around three a week and searches only on behalf of friends and family.

"I am seeing a lot more people who have a pathological anxiety about health triggered by what they have been reading on the internet and in magazines," says Dr Richard Stern, a consultant psychiatrist at St Anthony's Hospital in Surrey and the Priory in Roehampton. "There is such a proliferation of information that it makes it easier for people to convince themselves that they have recognised symptoms and that there is something physically wrong with them."

Certainly, it has become more difficult to avoid health paranoia. It's not just the internet - TV and the magazines are increasingly devoting themselves to illnesses and ways to stay healthy. Last week saw the launch of A magazine, devoted entirely to the subject of allergies. I defy anyone to read it without becoming convinced they have one.

But it is on the internet that our imaginations can really run wild. No one is sure quite how many sites are devoted to health - it is impossible to keep track - but it is estimated it now exceeds 150,000 with more being added by the week. They are entirely unregulated and can be posted by anyone - pharmaceutical companies, doctors, agony aunts and flaky crackpots. The most popular attract more than three million visitors a month.

"It is easy to get caught up in believing everything you read on there," says Fiona. "At one point, I logged on to a chat room on a multiple sclerosis site and was inundated with emails from people who had obviously lost the plot and thought they were dying from blood clots or something."

In America, a study last year by the market research company Harris Interactive revealed that 109 million adults (78 per cent of the population) had trawled the internet at least once in the previous 12 months to find out more about a medical topic, a figure that has doubled since 1998. Of those, around two thirds admitted they were regular users who have become reliant on the web for information on diseases, syndromes and general health; in other words, claimed the researchers, these people have varying degrees of cyberchondria.

"Mild health anxiety is very common. Many of us have concerns about unexplained bodily functions or symptoms at one time or another," says Professor Richard Mayou, a consultant psychiatrist at Oxford University's medical department in Warneford Hospital. "However, most people are satisfied when they get medical reassurance that nothing is seriously wrong." It is when a person remains convinced that they are ill despite a doctor's verdict and then persists in seeking a diagnosis, either professionally or through their own devices, that their concerns become something more serious. But it would be wrong to dismiss them as fakers, says Professor Mayou; in fact, they are dogged with elusive symptoms (palpitations, allergies, stomach pain and breathlessness are the most common) that suggest a real a medical problem.

It is because cyberchondriacs fervently believe they are physically ill that they get so frustrated when told they are not. As a result "doctor-shopping" - flitting from one surgery to the next - is a growing phenomenon in America among those who refuse to take no for an answer. There are signs that it is also happening here. "People who want confirmation that they are ill - a label - won't stop until they get it," says Dr Stern. "If one doctor doesn't give it, they'll go to another. Either that or they'll diagnose and treat a condition themselves."

Maria Blake, a PR executive from London, admits she has early symptoms of health anxiety. "I will read anything about medical issues that I can get my hands on, in print or on the net," she says. "I convinced myself that wheat and dairy were affecting my health and I've stopped eating them. I take a pile of vitamins every day because I think I am deficient. I am a yoga addict because I think I am too stressed. This has all arisen from stuff I have read."

She is a short step away from cyberchondria. A friend (let's call her Fiona) recently came home to find her husband looking ghostly pale and withdrawn. He had been off work with a bad cold (in his opinion, flu) and had spent much of the morning watching television. "When I asked him what on earth was wrong, he told me to sit down and proceeded to explain why he thought he had prostate cancer," says Fiona. "Apparently he had been watching a breakfast programme where a doctor had outlined the symptoms and had convinced himself that he fitted the bill. The main reason seemed to be that he had been going to the toilet more often than usual. He spent the rest of the day on the computer, trying to find out as much about the disease as he could."

A visit to his GP showed nothing was wrong. The same goes for the chest pains and mysterious rash he has since developed, yet he continues to suspect that these are the symptoms of an undiagnosed disease and continues to search for clues on the web.

Ironically, in many cases, health anxiety develops into an illness in its own right for which treatment, usually cognitive behaviour therapy (CBT) and stress management, may be prescribed. People who are genuinely so distressed and worried about unexplained symptoms that they fasten them to an illness need to be taught to change their misconceptions about disease.

"It can be difficult to persuade people at first that they need psychological rather than physical treatment, but getting them to alter their beliefs about what they think they have got can be pretty powerful," Professor Mayou says. "A lot of the time, their anxiety has arisen from the misinterpretation of a minor physical sensation for which there could be a very simple explanation. If you can help them accept that, they are on the road to recovery."