Scientists' alert over side effects of lithium

Lithium is used to prevent mood swings caused by bipolar disorder, combating mania and treating severe and recurring bouts of depression.

But if patients become dehydrated or start taking other medicines that affect levels of lithium in the blood, the drug can prove dangerous and even fatal.

Experts from the National Patient Safety Agency last year issued an alert about the drug following a series of deaths and cases of serious harm, describing its use as "error-prone".

They ordered hospitals to sort out their procedures and prevent more mistakes by the end of this month.

Now researchers from Leeds University have worked with patients to test a new national guidance booklet to be given to all those taking the drug to ensure they can understand key messages.

Pharmacy professor Theo Rayner, who led the research, said: "It is very important that all patients prescribed lithium are monitored correctly and told how to recognise early signs of any problems.

"This booklet uses clear, unambiguous language to tell patients how they should take their medicine, the importance of regular check-ups and blood tests and what warning signs to look out for."