Cisplatin, a formidable anticancer treatment, is used for several varieties of
cancer. There are, however, many cases in which treatment must be abandoned due to a decrease in the patient's quality of life from loss of appetite associated with
vomiting and
nausea. There is a moderate degree of improvement in prevention of
cisplatin-induced
nausea and
vomiting when
serotonin (5-HT) 3 receptor antagonists,
neurokinin 1 receptor antagonists, and
steroids-either alone or in combination-are administered. The mechanism of action for
anorexia, which continues during or
after treatment, is, however, still unclear. This
anorexia is, similar to the onset of
vomiting and
nausea, caused by the action of large amounts of
5-HT released as a result of
cisplatin administration on tissue
5-HT receptors. Among the
5-HT receptors, the activation of 5-HT2b and 5-HT2c receptors, in particular, seems to play a major role in
cisplatin-induced
anorexia. Following activation of these two receptors, there is reduced gastric and hypothalamic secretion of the appetite-stimulating
hormone ghrelin. There is ample evidence of the usefulness of exogenous
ghrelin, synthetic
ghrelin agonists, and the endogenous
ghrelin signal-enhancer
rikkunshito, which are expected to play significant roles in the clinical treatment and prevention of
anorexia in future.