The only possible negative symptoms from excessive DHEA that I' m aware of result from its being a precursor of testosterone and oestrogen. After it is transformed into these sex hormones, it may be a factor in symptoms of hormonal imbalance - cycle irregularities, aggression, acne, mood swings and so on. It has to be said, however, that these symptoms have only emerged in people who supplement high levels of DHEA (in the US, it is available over the counter as an anti-ageing and anti-stress hormone).

I don' t know of any direct ways to keep DHEA on an even keel, other than generally supporting your adrenals. To do this, try to reduce your levels of stress by relaxing more; cut out stimulants such as coffee, tea, chocolate, cigarettes and sugary, refined foods that will send your blood sugar on a rollercoaster; and supplement with B vitamins and C, plus Siberian ginseng.