Hypochondriasis is a preoccupation with fancied bodily illness.

• hypochondriacal patients suffer from the fear or conviction of having a serious disease, and their fear or conviction is based on a misinterpretation of bodily symptoms (DSM-IV; American Psychiatric Association, 1994). Although appropriate medical examination has given no support to their ideas, the fear or conviction remains
• patients with hypochondiasis develop a characteristic behavioural and cognitive pattern, in which they gradually seek more reassurance, but nevertheless become more and more anxious
• it is a condition that is usually a neurosis but may very occasionally be delusional

Hypochondriasis may co-exist with actual physical disorder; the important feature is that the patient's concern is out of proportion to any physical disorder and not justified.

Hypochondriasis may occur in neurotic depression, anxiety, obsessional disorder and hysteria. Schizophrenic patients may show a bizarre form of hypochondriasis. Also an essential hypochondriasis may exist.