It is, indeed, alarming that there has been an estimated 12-fold increase in the number of Scottish children diagnosed with attention deficit hyperactive disorder (ADHD) in a little more than a decade (December 19). Dr Chris Steer of NHS Fife is probably correct to state that this rise is due to "catching-up" rather than "over-prescribing"; however, there is a distinct possibility that this may not be wholly accurate as the dividing lines between ADHD, behavioural problems and bipolar disorders, especially in a very young child, can be difficult to discern. However, in very young children, ADHD presents similar symptoms to bipolar disorder and the antidepressants used to treat ADHD can make bipolar symptoms worse. This makes a prompt and accurate diagnosis essential.

The original bipolar disorder was later joined by three new, defined conditions, the fourth of which included patients with bipolar-like symptoms that did not fit the other three diagnostic criteria. This itself may be the reason for the increase in the number of children being diagnosed with this disorder also.

Although this may be a genetic disorder, the evidence has not been clearly defined. In addition, the anti-depressant drugs some patients receive for other psychiatric conditions may also trigger a bipolar disorder at an earlier age and with greater severity than those not prescribed such drugs.

Dr Steer correctly states that medication is not a stand-alone treatment, but an accurate diagnosis for each condition is the bed-rock on which the patient's future depends.

Ian F M Saint-Yves, Dunvegan, School Brae, Whiting Bay, Isle of Arran.