Diarrheal disease is one of the major causes of morbidity and mortality in children under five. Disease is treated symptomatically with oral rehydration (ORS) as a basic measure. In children with severe zinc deficiency, diarrhea is common and responds quickly to zinc supplementation. Zinc supplementation may also helpful in diarrheal children without zinc deficiency. Effectiveness of zinc was proven in developing countries but was not in Europe. Objective of our study is to assess whether zinc supplementation given with probiotics and ORS is effective in acute diarrhea in children in Poland.

A double-blind, placebo controlled trial

- We are going to enroll 256 patients (aged > 1 months to 36 months) with acute watery diarrhea defined as 3 d or more watery stools per day lasting not less than 1 day and not longer than 5 days.

Exclusion criteria:

severe dehydration (> 10%) Coexisting severe infection (E.g. Sepsis, pneumonia, meningitis) Immune deficiency Chronic digestive tract disease (e.g. celiac diseases, food allergy) Therapy with Antibiotics

Patients will be randomly assigned to 2 groups to receive: (a) zinc sulfate 10-20 mg/day for 10 days plus probiotics for 5 days (b) placebo for 10 days plus probiotics for 5 days. Patients will be observed in ambulatory or in the hospital (if necessary) and followed up for 15 days.

Randomization 1:1

Inclusion Criteria:

• Age 1-36 months
• Acute diarrhea defined as 3 or more watery stools per day
• Informed consent (parents)

Exclusion Criteria:

• Severe dehydration (> 10%)
• Coexisting severe infection (e.g. sepsis, pneumonia, meningitis)
• Immune deficiency
• Chronic digestive tract disease (e.g. celiac diseases, food allergy)
• Antibiotic therapy