Have I really turned the iron off? This is the kind of question that comes up repeatedly, even when you know very well that the iron has been turned off. Fears of this kind can mutate into obsessive-compulsive disorder (OCD). Some people are so frightened of catching a virus, for example, that they draw back from shaking hands and are constantly washing their hands - a classic case of OCD.
This kind of behaviour urgently needs professional attention, says Frank Bergmann of the German association of neurologists. Early therapy can prevent the onset of a range of symptoms, like constant shaking, sweating and palpitations.
OCD can reveal itself in many ways. Persistent sexual obsession may also be an indication. Sufferers are constantly thinking about how to carry out certain acts in precisely the right way, Bergmann says. Many of those affected tend to hide their disorder for fear or shame, with the result that they often become depressed, because they fully realise how absurd their behaviour is.
As a result, anti-depressive medication can be particularly effective in combination with behavioural therapy in treating the condition, which affects up to 2 per cent of the population.