Herman Koch's doctor novel should carry a health warning

"I told my doctor that I was about to write a new novel and that the narrator and protagonist of this book, Summer House With Swimming Pool, was a doctor, a popular doctor with many celebrity patients. My GP also has a list of patients who are rich and famous - filmmakers, actors, TV stars, playwrights, novelists. So he asked, 'Oh, it's not me, is it?'"

"'No,' I lied because a writer should always lie - oh yes, even to his wife, his family. 'No, it's not you,' I said. But what I borrowed from him was his list of patients." Among other things.

Summer House With Swimming Pool's unreliable narrator, Dr Marc Schlosser, informs us within three pages of the novel, "Occasionally I'll ask someone to undress behind the screen, but most of the time I don't. Bodies are horrible enough as it is, even with their clothes on. I don't want to see them..." There is much more in this sinister vein as the "good doctor" tells how much he despises his patients, how they repulse him.

When the book was published in Holland, Koch's doctor told him. "These are all the things I'd never be able to say aloud."

"Then he said, 'Thank you,' which pleased me because I want to write about what people are really thinking," Koch reveals when we meet at a London hotel - he's in town to meet a "big-name" film director keen to film the novel.

Perhaps Summer House With Swimming Pool - tipped as this year's beach must-read - ought to come with a health warning? After reading it, I fear I may never visit a doctor again. When I say this, Arnhem-born Koch laughs, adding that some reviewers in the US, where the book came out last month, have warned that his novel should not be read within three weeks of any medical appointment.

Koch, a former actor, absurdist comedy scriptwriter and TV star in the Netherlands, says he knew instantly that his protagonist would be a doctor. "I always had my first sentence, 'I am a doctor.' The storyline came later. I also knew that he would have patients who are successful, particularly in the creative arts. The status of the doctor, indeed the prestige of the profession, has diminished a lot in the last 50 or 100 years, so I kept thinking how some of those in such circles might think they are better than a simple general practitioner.

"All these artists, who consult Marc, might even feel a little contempt for him. After all, he's not a surgeon. So a doctor, who is not respected as he might once have been but who might save lives, is held in lower esteem than actors or painters or TV comics. So I was thinking about all of this, how a doctor might become fed up with his patients; then I thought these people will do something to him which humiliates him and he'll seek revenge and show them he is the better man."

"Do you know, I have only just thought of this," says Koch after a moment's pause. "But there is a story by Chekhov called, in English I think, Butterfly [The Grasshopper], about the wife of a doctor having an affair with a painter. She's never with her husband, who is thought a silent bore in artistic circles. Then the painter ends the relationship, and the doctor saves a child's life but becomes ill with the same infection. He's dying when she realises that all these artists do not have one per cent of value that her husband had. She's wasted her whole life because he was a good man.

"I read it when I was 18 years old - I studied Russian literature before dropping out of university - and then I re-read it maybe ten times over the years. I was always thinking that I'd do this kind of story in a novel. It turned out completely different."

And how. The first chapter of Koch's novel ends with the widow of a patient arriving in Marc's office and spitting in his face. ("Rage makes for ugly widows.") She is the glamorous Judith Meier and her husband, Ralph, was a huge star, an egotistical boor, who consulted Marc, who is known to be generous with prescription drugs.

The pair become friends, despite the fact that the predatory Ralph eyes up Caroline, Marc's lovely wife, while handsome Marc embarks on an affair with Judith. In flashbacks, we hear of the holiday from hell that Marc's family - he has two beautiful, daughters - shared with the Meiers and their two sons. A violent act is committed and we are plunged into the deep end of noir fiction. For, as Koch points out, people rightly fear doctors for all sorts of reasons.

Marc - who is more Harold Shipman than saintly Chekhovian - is not a good man. He's as unsympathetic as Paul, another dubious narrator, who relates The Dinner, which won the prestigious Dutch literary prize, the NS Publieksprijs, in 2009. The book, currently being adapted for a film to be directed by Cate Blanchett, is structured around a restaurant meal - Koch has fun satirising the snobbery of high-end dining, giving a new meaning to going Dutch. Paul and his wife meet his brother, who is hoping to become prime minister, and his wife, to discuss how they can protect their teenage sons, who have committed a senseless act of violence.

The novel asks how far middle-class parents will go to protect their children and has drawn comparisons with Christos Tsiolkas's The Slap. "I'm drawn to the idea of moral codes shattering, questioning whether political correctness is the right path. Also, my wife, Amalia Rodriguez, who is Spanish, and I have a 19-year-old son, Pablo. He was 11 when I began writing The Dinner, and as he reached his teens I was wondering as all parents do, what he's up to.

"My narrator in The Dinner, which is popular with young people and on the school syllabus in Holland, snoops through his son's smartphone. Not something I'd ever do, though I've been tempted," he confesses, adding that he's explored morality in previous novels, such as Odessa Star (2003). However, his eighth novel, Dear Mr M, already a bestseller in the Netherlands and which will be published here next year, eschews middle-class family values. It has, though, the same ironic wit and satirical take on the world as his previous work, he promises.

Which, Amsterdam-based Koch admits, owes a great deal to the hit comedy Jiskefet (Trash Can), a sort of Dutch Little Britain-style show, which he co-created and performed. "It ran on TV for 15 years, then it was time to stop," he says, saying that he wanted to write fiction from an early age. His first book, The Passerby, a collection of short stories, came out in 1985. Acting, although he claims he wasn't a real actor, informed his characters.

Educated at the Montessori Lyceum in Amsterdam, he was not so much expelled as requested not to return. He was the only child of a jeweller mother and newspaper publisher father, although he has older half-siblings from his father's previous marriage. He was 17 when his mother died, 25 when his father died. His father, who wrote a couple of children's books, worried about his son's "tarnished" education and never lived to see his international acclaim.

Now a veteran "performer" at literary festivals across the globe - Koch has 37 international publishers after The Dinner sold 1.5m copies worldwide and became the most translated Dutch novel ever - he relishes meeting readers. Their reactions vary according to the mores of different countries. "In America, they worry a lot about political correctness - the New York Times reviewer described The Dinner's morality as 'really sickening'. Ha, ha! Mainly, though, people like to discuss moral issues. In Holland, they like to read about disagreeable characters so long as they're interesting."

He has a challenge for his audience at the Edinburgh International Book Festival; it's one he throws out at every event. "I offer a prize for the most shameful question." He's yet to be shamed by any question asked anywhere. Come on, Edinburgh, scandalise the merchant of menace.

Summer House With Swimming Pool by Herman Koch is published by Atlantic, priced £12.99. Herman Koch discusses European fiction with Norwegian writer Tore Renberg at the Edinburgh International Book Festival on August 11