The clinic that made its name treating tired and emotional celebrities is under fire for selling 'cures' for text-message and spread-betting addiction. By Sophie Goodchild

It is the most famous name in British psychiatry and the clinic of choice for troubled and addicted celebrities such as Michael Barrymore, Paula Yates and Caroline Aherne. The Priory has pioneered the treatments for our times, for drug, alcohol and even sex addictions. But its latest range of therapies, tailored to the way we live now, for illnesses ranging from mobile-phone texting addiction to compulsive spread-betting, is under attack. One critic even goes so far as to accuse the Priory Group of operating its businesses "like a McDonald's restaurant" and condemned its "cynical" commercial drive to sell therapy to the mass market. The Priory Group, which owns the flagship 90-bed clinic housed in a Gothic mansion in Roehampton, Surrey, is also fending off attempts by luxury health spas to lure away its A-list clients.

The owners of Champneys, the health resort operator which now offers counselling and detox programmes, have hired Dr Mosaraf Ali, a well-connected medical specialist whose clients include Prince Charles, as their holistic expert in a deliberate move to take business away from the Priory. George Best and Sophie Anderton are among the top names who have checked themselves in.

Treating the minds of the addicted and clinically depressed has made Dr Chai Patel, the chief executive of Priory Group, a wealthy man. His earnings have been estimated at more than £400,000 with an £8m bonus last year when the Priory Group was subject to a management buyout. Its turnover was approximately £120m in 2002.

An ardent supporter of public-private partnerships, the 48-year-old trained as a doctor and then became a City banker. He is also influential in political circles, advising the Government on its healthcare policy, and in 1999 donated £5,000 to the Labour Party. His aim is to bring the Priory brand to the masses. Last month, Priory Group launched a new "lifestyle" addictions service to treat not only drug and alcohol abusers but also obsessive text-messagers and online spread-betters.

"The Priory healthcare team has created a new range of addictions treatment programmes designed to meet patients' changing lifestyle and medical needs," reads the promotional release. Cocaine-snorting execs on the verge of a breakdown will no longer have to "out" themselves to friends and colleagues by taking 28 days to detox. Instead, they will be able to choose from seven-day in-patient treatment or attend sessions after work.

There are also plans to release the first Priory relaxation CD featuring advice from their top therapists, a video, and self-help books to bring the Priory brand to the masses and to spread its message of "hope, healing and sanctuary". The Priory has also hired the marketing agency Branded for an advertising campaign aimed at young professionals with alcohol problems. One advertisement placed in the national press depicts a smudged list of comments made by drinkers, followed by the line: "If this is all you can remember about last night, call the Priory."

The healthcare company, which treats more than 6,000 addicts a year, says it is committed to destigmatising mental illness and is merely ahead of the competition in identifying the latest trends in addiction. High-earning clients such as Kate Moss and Ronnie Wood expect to pay more than £2,000 for a week's stay, but half of the patients treated by the Priory are referred by the NHS. Karen Croft, spokeswoman for the Priory Group, said its charges for NHS patients were "comparable with or below" official guideline prices and that patients referred to them from the NHS required more intensive one-to-one sessions than private clients.

"We offer a very intensive, tailor-made service which you can't get care of the NHS," she said. "Every patient is treated as an individual. What we want to do is to raise the issue of addiction. We have seen a rise in behavioural addictions. Gambling is a well-recognised behavioural addiction. Sex addiction is an issue. If we notice a trend, it's a genuine trend."

But the British Association of Counselling and Psychotherapy (BACP) said patients would be better off throwing "the mobile in the river" than attending a month of therapy sessions.

"Counsellors and psychotherapists are puzzled by this labelling process," said Phillip Hodson, a fellow of the BACP. "There is no physiological basis for this use of the term 'addiction' ... Labels like 'sex addiction' and 'love addiction' are nothing more than a response to the body's own adrenaline production."

In his opinion, people are paying for the kudos attached to the Priory name.

"Their service is first class and they use a lot of first-class therapists - the question is what's the actual bill," he said. "They've noticed the publicity they're getting and they're realising the investment. I don't think it's a question of making money, it's a question of how much. If therapists on average cost X pounds or less and a private clinic costs X more, you have to ask why. The Priory is very expensive."

Frank Furedi, professor of sociology at the University of Kent and author of Therapy Culture, which criticises dependency on therapy, said the Priory was run as a money-making concern "in the same way as a McDonald's".

"They're always in the business of inventing new illnesses, by framing experiences most of us have under an illness label," said Prof Furedi. "They've moved away from focusing on the very rich to a mass market. The more we hear that addiction is a penalty for life, the more it creates a massive public health problem."

Alan Franey, former director of Broadmoor hospital, said that the NHS, unable to cope, was offloading its acute mental health patients on private sector companies such as the Priory Group.

"It's worrying when any private organisation jumps at what can be perceived as a money-making opportunity," said Mr Franey, who is now director of the Buckinghamshire Association for Mental Health. "Training in psychiatry for GPs is pretty poor, and if someone said they wanted to be referred to the Priory for [addiction to] texting they would probably refer them."

Oliver James, a trained clinical psychologist and author, questioned the fact the Priory labelled text-messaging as an addiction. "It's cynical because they [the Priory] are trying to get publicity for their profit-making institution," he said. "What they should do if they really want to help mental health is set up a charity to publicise the problem."

Additional reporting by Peta Bee, Andrew Johnson and Hannah Forbes Black