Every new drug licensed in Britain will be given a “suicide rating” under proposals for a big shake-up in the rules governing pharmaceutical development. European regulators are also to require pharmaceutical companies to include a comprehensive suicide assessment into trials of new medicines.

The reform, based on a system adopted recently in the United States, has been fuelled by a growing body of evidence that drugs that affect the brain can heavily influence behaviour through seemingly innocuous changes in body chemistry. Medicines to treat acne, swelling, heartburn, pain, obesity, high blood pressure and cholesterol, bacterial infections, smoking and insomnia have all been associated recently with psychiatric problems. There have been warnings about the potential side-effects of Acomplia, an antiobesity drug, Roaccutane, an acne treatment, and Champix, an antismoking medication, which together have been prescribed to more than 60,000 patients in Britain.

Acomplia, also known as rimonabant, is designed to suppress the appetite but has been reported to more than double the rate of suicidal symptoms. Champix (varenicline), a drug that negates the pleasurable effects of smoking, has also received 1,513 reports of adverse reactions, including 62 reports of suicidal feelings.

David Roberts is one of 26 people said to have killed themselves while taking Roaccutane. The “cheerful” 20-year-old was found hanged near his Liverpool home three months after he began taking the drug.

The European Medicines Agency (EMEA), which regulates all drugs, has sent letters to an undisclosed number of drug companies requiring them to analyse their data again, using the system approved by the US Food and Drug Administration (FDA).

Discussions have also taken place between Kelly Posner, the designer of a suicide risk-assessment system, the EMEA and the pharmaceutical giants. They are due to meet in April to discuss how to introduce a suicide risk questionnaire, which has already been translated into 80 languages, into future drug trials.

“All the players, the FDA, EMEA, representatives from the drug companies, will be at the meeting to discuss how to move forward,” Dr Posner, a research scientist based at Columbia University, New York, told The Times. “I’ve been getting requests from clinics and authorities in Europe asking how to implement the study. It’s really moved the field in that way. Hopefully this will be the first step to broadening the study across Europe.”

Dr Posner and her team spent months creating a comprehensive questionnaire known as the Columbia Suicide Severity Rating, in which patients’ actions can be classified as either suicidal or nonsuicidal.

The questionnaire takes less than five minutes to administer and looks for four different types of suicidal behaviours. Each behaviour is rated for its severity and the drug is given an overall “suicide rating” out of 23.

The system could also vindicate the reputation of the class of antidepressant drugs known as selective serotonin reuptake inhibitors (SSRIs), which are no longer prescribed to people under 18 because of fears that they encourage suicidal thoughts in this age group.

“All the previous studies that these risks were based on were not set up to assess suicide risk,” Dr Posner said. “What we can learn from them is very limited. After the warnings [about SSRIs] were issued there was a 22 per cent decline in prescriptions in the US and in parts of Europe. There is a concerning correlation between reduced prescriptions and increased suicide.”

The Medicines and Healthcare Products Regulatory Authority, the British watchdog, said yesterday that it would follow the EMEA if the Columbia test became more widely used. “The EMEA would probably implement the change through a directive, which we would be bound to follow,” a spokeswoman said.

Drugs with known links to depression

Acomplia, an antiobesity drug

Dianette, a treatment for severe acne

Strattera, a medicine used to treat attention deficit hyperactivity disorder

Interferon alfa, used to treat certain cancers and hepatitis B

Roaccutane, an acne treatment

Zarontin, drug used to control epileptic seizures Source: British National Formulary

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