The UK National Institute of Health and Clinical Excellence (NICE) has delivered its first guidance on the diagnosis and treatment of patents with obsessive-compulsive disorder, in a move that could encourage prescribing of drug treatment for patients with more severe forms of OCD.

The guidance is a major advance for OCD patients, who typically have to wait up to 17 years before diagnosis and the start of therapy, according to the NICE. It sets out criteria for diagnosing the condition, and recommends that patients with milder forms of OCD receive behavioural therapies, with drug treatment with selective serotonin reuptake inhibitor (SSRI) antidepressants reserved for those with more severe symptoms.

One to two people in every 100 have the condition, in which sufferers have irrational thoughts and ritualistic behaviour, such as excessive hand washing. The guidelines also cover body dysmorphic disorder (BDD), an unrelated condition which causes sufferers to become obsessed with what they consider to be physical defects. BDD sufferers often seek surgical corrections to their perceived problem. It affects 0.5 to 0.8 per cent of the population.

NICE chief executive Andrew Dillon said: "The condition often goes unrecognised and untreated and we hope the guideline will help raise awareness of this distressing condition which in most cases can be effectively treated."

Piers Watson, chairman of the OCD Action charity, said the guidelines, while welcome, are only a first step in making appropriate treatment available to all sufferers. “How quickly can the yawning gap be bridged, that presently exists between the many sufferers and the few available healthcare practitioners specifically trained to treat these illnesses? This is now the challenge,” he added.