Some probiotic preparations reduce symptoms of child diarrhoea whilst others have little effect, find Italian researchers.
Reporting in this week's British Medical Journal, the team from Naples University tested the effectiveness of five probiotic preparations on a group of 571 children aged 3-36 months all with acute diarrrhoea between 1999 and 2000.
The children were randomely allocated to one of six groups - the sixth being a control group receiving only oral rehydration solution.
After five days treatment, only two of the probiotics - Lactobacillus rhamnosus strain GG and a mixture of Lactobacillus delbrueckii var bulgaricus, Streptococcus thermophililus, Lactobacillus acidophilus and Bifidobacterium bifidum - were found to be effective.
Both preparations shortened median duration of symptoms to 78.5 hours and 70 hours respectively whilst controls had symptoms for 115 hours. One day after treatment these two had also reduced the daily number of stools and stool consistency was different than in the other three groups and controls. The other three (Saccharomyces boulardii; Bacillus clausii; and Enterococcus faecium SF68) has no effect on diarrhoea and symptom duration was the same as for controls.
All five probiotics were avaliable only from chemists. But, as in other countries, are sold as food supplements not as medicines so only their safety not their efficacy is needed for marketing them, explained the authors.
Parents would have little awareness of which bacterial strains were more effective, they said, as evidenced by the fact that only one of the two most widely used probiotic brands in Italy was effective (L rhamnosus strain GG) whilst the other was not (Bacillus clausii).
Since gaining increasing credibility for treatment of gastroenteritis and other diarrhoeal diseases, clinicians have increasingly prescribed probiotics as adjuvant treatment for acute symptoms.
Assistant Professor of Paediatrics Roberto Berni Canani, who led the study said: "We believe that probiotics should be classified as drugs, and physicians should select preparations for which evidence of efficacy, in a given clinical condition, is supported by solid data."
Bmj.com; doi:10.1136/bmj.39272.581736.55