Hi. Thanks for your query. Noted the history and understood your concerns. Since your son is only 11 months old, self medication should be avoided and you should consult a Pediatrician so that a proper clinical evaluation, prescription based antibiotic as per the cause found and the reports of the stool and blood test. continuing Zincovit is fine. Add on probiotics. The cause may be infection during feeding. If the baby is bottle fed, proper sterilization of the bottle the nipple, spoon and all the material related to feeding is very important. Also send stool for intolerance for lactose or so. Stool culture helps further. If there is an evidence of an intestinal infection the Pediatrician would advise an appropriate medications.