The findings of this review indicate that the number of systemic and topical drugs used for the different subforms of pruritus is increasing. Different interventions have been shown to be effective in the treatment of pruritus of different origins. Nevertheless, an optimal therapy for pruritus is constrained due to the limited understanding of crucial itch mediators and receptors in the various subforms of itch. Ideal antipruritic therapies are still lacking, especially for palliative care patients.
This systematic review also indicates that there is insufficient evidence to give any concrete recommendations regarding treatment of pruritus in palliative care patients. Due to the very small sample sizes and poor methodological quality of the majority of studies that were included, the results of this review need to be interpreted with caution. Furthermore, the generalizability is questionable. Additional studies, and particularly carefully designed treatment trials, are needed to provide valid evidence for adequate treatment of pruritus in palliative care patients.
A controlled trial of ondansetron in the pruritus of cholestasis.
In patients with pruritus of cholestasis, response to conventional drug treatment may be unsatisfactory. Activation of 5-hydroxytryptamine receptors on dermal sensory nerve-endings plays a role in the perception of pruritus. The 5-hydroxytryptamine(3) receptor antagonist, ondansetron, has been used in the treatment of pruritus of cholestasis, but there are few controlled data.
                To determine whether ondansetron is effective in treating the pruritus of cholestasis.
                A total of 19 patients with resistant pruritus were randomized, double blind, to receive either ondansetron 8 mg or placebo as a single intravenous bolus, followed by oral ondansetron 8 mg or placebo twice daily for 5 days. Patients' perception of pruritus was recorded hourly using a visual analogue scale, and scratching activity measured by means of a piezo-electric crystal attached to the fingernail.
                Mean pruritus score using visual analogue scale and scratching activity were reduced on the first treatment day compared with baseline in both the ondansetron and placebo groups (P < 0.05), but there were no significant differences in mean pruritus perception or scratching activity between the two groups.
                Ondansetron was of no benefit in this group of pruritic patients during short-term treatment.