IF FISH oil genuinely turns out to help relieve the symptoms, and hence the suffering, of schizophrenia it will be a remarkable clinical advance.

But it is being promoted on the false and dangerous premise that all existing drug treatments for the devastating condition have severe side effects. Older drugs do have side effects but newer ones cause far fewer problems.

The worry expressed by psychiatrists is that hopes are being raised among patients about fish oil before the evidence is in. The fish oil story has been energetically promoted on the Internet by excited patients and to the media by Scotia Pharmaceuticals, the drug company which has funded trials in Aberdeen.

Professor Rob Kerwin, of the Insitute of Psychiatry, is one who remains unconvinced. He says more and better evidence is required and fears that patients who are already reluctant to take drugs which are effective may be further deterred from using them.

The risk of suicide is high in schizophrenia and the danger of deterring patients from taking their correct treatment is serious.

New anti-psychotic drugs which have come on to the market in the last decade and have fewer side effects are only being taken by one in four of those who could benefit from them, he says.

"Suicide rates can now be dramatically reduced by novel anti-psychotics. We think they are very important."

The message to patients is that experimenting with fish oil is unlikely to expose them to any harm. But they should not, on any account, discontinue their current treatment without medical advice.