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8 Other therapies

Introduction
A range of other therapies have been proposed for use in gastroenteritis. These have focused on
alleviating vomiting and diarrhoea. They have included a range of anti-emetic and antidiarrhoeal
agents. Benefits have also been attributed to certain micronutrients and dietary fibre. In recent
years there has been considerable interest in the possible role of probiotics.

Clinical question
Which interventions (other than fluid therapy and antibiotic treatment) are effective and safe?

Various medical interventions were considered under the following category headings:
1. anti-emetics
2. antidiarrhoeals
3. micronutrients and fibre
4. alternative and complementary therapies
5. probiotics.
A search was performed with no restrictions on date and this returned 1245 references. The titles
and abstracts of these were appraised and 163 papers were identified as potentially relevant to
the guideline and were obtained in full copy. Of these, 33 were relevant and were included in
this chapter. A further two papers were identified from updating searches. 160,161

8.1 Anti-emetics

Many children with gastroenteritis experience vomiting, particularly in the early phase of the
illness. This is a distressing symptom. Importantly, it is a major factor in leading to failure of ORT.
If vomiting could be treated effectively then there might be a reduction in the use of IVT. Various
anti-emetic agents have been used to prevent or reduce vomiting in children with gastroenteritis.
The phenothiazines are dopamine antagonists and act centrally by blocking the chemoreceptor
trigger zone. They are used to prevent or treat vomiting associated with drugs such as opioids,
general anaesthetics and cytotoxics. Unfortunately, severe dystonic reactions sometimes occur
with phenothiazines, especially in children. Metoclopramide is an effective anti-emetic and its
activity closely resembles that of the phenothiazines. Metoclopramide also acts directly on the
gastrointestinal tract and it may be more effective than the phenothiazines for vomiting associated
with gastroduodenal disease. 162 As with the phenothiazines, metoclopramide can induce acute
dystonic reactions involving facial and skeletal muscle spasms and oculogyric crises. These
dystonic effects are more common in the young. Ondansetron is a specific 5HT antagonist
3
which blocks 5HT receptors in the gastrointestinal tract and in the central nervous system, It has
3
been shown to be effective in the treatment of vomiting in patients receiving cytotoxic agents for
cancer. Dexamethasone also has anti-emetic effects and is used to prevent vomiting associated
with cancer chemotherapy. In this context it may be used alone or with other anti-emetics such
as metoclopramide or a 5HT antagonist.
3
Evidence overview
Five trials were identified as relevant to this review. 160,161,163–165
Four of these were conducted in the USA 160,161,163,164 and one in Venezuela. Two trials had three
165
treatment arms 161,165 and the rest had two. Across the five studies, data from 639 children (aged
6 months to 12 years) suffering from gastroenteritis were collected. The following comparisons
were investigated:

• oral ondansetron versus placebo
• IV ondansetron versus placebo

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