5-HT and physical illness.

The discovery and clinical evolution of 5-HT re-uptake inhibiting drugs are reviewed. From the widespread distribution of 5-HT in bodily systems and the range of effects and side effects reported, it is concluded that these and other drugs active on the 5-HT system are likely to have beneficial effects on a range of other physical conditions coincident and co-morbid with the affective disorders. Clinical vigilance may therefore be repaid with serendipitous discoveries.