Doctors are ignoring health watchdog guidelines and regularly prescribing youngsters with an antidepressant linked to suicide and overdose, new figures show.

Under guidance from The National Institute for Health and Care Excellence (Nice) antidepressants should be a last resort for under-18s, and then only fluoxetine (Prozac) is recommended.

But a study by the university of Swansea found 40 per cent of youngsters who need drugs are being prescribed citalopram, even though it carries a warning that it can increase suicidal thoughts and behaviour in the under-24s.

Recent studies have also found the drug does not work for children and is highly toxic in overdose.