Page 143 - 15Diarrhoeaandvomiting

Diarrhoea and vomiting caused by gastroenteritis in children under 5 years

Six trials administered zinc alone 175,181,183–186 and two trials administered zinc with a multivitamin
preparation. 177,182 In one trial 181 the placebo group received vitamin C while the intervention
group did not. The outcomes measured were duration of diarrhoea, stool output, hospitalisation,
adverse events (vomiting) and death. Not all of the studies included reported all the outcomes.
One RCT (n = 81) 181 was aimed at determining the effect of oral zinc supplementation on
the duration of acute diarrhoea in young children. Participants were children aged from 3 to
60 months suffering from diarrhoea for less than 7 days and with, at least, mild dehydration.
Children were hospitalised and followed for 5 days or until resolution of diarrhoea. [EL = 1−]
Another RCT (n = 287) 182 examined the clinical benefit of zinc supplementation as an adjunct
to ORT on stool output and duration of diarrhoea in children with non-cholera diarrhoea.
Participants were outpatients aged between 3 and 36 months, with diarrhoea for less than
72 hours and mild dehydration. [EL = 1+] The findings showed that there was no statistically
significant difference in the proportion of children with diarrhoea by the 5th day from the start
of the study in each of the study groups. The geometric mean of the total stool output in the
intervention group was 111 g/kg (95% CI 86 to 147 g/kg) and in the placebo group was 148 g/kg
(95% CI 116 to 190 g/kg). The effect size favoured the group receiving the zinc supplementation
(ratio of geometric means = 0.69; 95% CI 0.48 to 0.99).
Another RCT (n = 275) 175 compared two different doses of zinc supplementation (5 mg and
20 mg of zinc acetate) with placebo on the duration of diarrhoea and stool output in infants
with acute diarrhoea. Participants were male infants aged between 1 and 6 months, hospitalised
and with diarrhoea for less than 3 days. [EL = 1+] The trial reported the geometric mean and
confidence intervals for stool frequency and total stool output. There were no statistically
significant differences in either outcome between the groups receiving 5 mg zinc, 20 mg zinc or
for those receiving placebo.
A multicentre randomised controlled trial (n = 1110) 183 assessed safety and therapeutic effects of
providing zinc supplementation to children suffering from diarrhoea. It compared the impact of
administering 10 mg of zinc sulfate per day for 14 days with that of placebo for the treatment of
acute diarrhoea. The participants were outpatients aged 1–5 months. [EL = 1+]

Another RCT (n = 1067) 184 was aimed at determining whether daily zinc supplementation was
associated with an increase risk of vomiting in children with diarrhoea. The study compared
20 mg of zinc supplementation per day for 10 days with placebo. Participants were young
children aged between 3 and 59 months with diarrhoea and admitted in hospital or in the
outpatient clinic. [EL = 1+]
Another RCT (n = 50) 185 assessed the impact of zinc supplementation on the duration of diarrhoea
and stool frequency in children with acute dehydrating diarrhoea. It compared the administration
of 40 mg of elemental zinc with the administration of placebo in children aged 6–18 months.
Participants were hospitalised and followed until recovery. [EL = 1−] It was reported that no
vomiting occurred during the follow-up in either group.
Another RCT (n = 947) 177 was aimed at evaluating the effects of daily supplementation with 20 mg
of elemental zinc on the severity of acute diarrhoea. The study compared the administration of
zinc with the administration of placebo. Participants were children aged from 6 to 35 months
and who had diarrhoea for less than 7 days. All participants enrolled received multivitamin
supplementation. [EL = 1+]
Another study (n = 899) 186 was designed to measure the impact of daily zinc supplementation
on the duration and severity of acute diarrhoea in children. The trial also assessed the effect
of administering zinc with vitamin A but only the zinc-supplemented group and the placebo
group have been considered here. Participants were children aged between 6 and 35 months
who presented with diarrhoea for less than 96 hours. [EL = 1+] The proportion of children with
diarrhoea by the 3rd day of follow-up was reported. It showed a statistically significant difference
favouring the group that received the zinc supplementation (27% of children with diarrhoea)
when compared with the group receiving the placebo (35% of children with diarrhoea) (RR 0.75;
95% CI 0.61 to 0.91). When the two treatment groups were compared, the ratio of the geometric
means of the number of stools in the first 4 days of follow-up showed a statistically significant
difference that favoured the group receiving the zinc supplementation (RR 0.91; 95% CI 0.85 to
0.97). Vomiting was found to be significantly higher in the zinc supplementation group (16%)

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