Hi there, Thanks for using HCM. Zentel contains albendazole. It is used to treat worm infestation. Some of the common side effects are abdominal pain and vomiting. If your baby is vomiting persistently, he is prone for dehydration. So in case of persistent vomiting, take him to doctor immediately. If the vomiting has stopped, there is no need to worry. You can give him enough fluids to keep him well hydrated. I hope that answers your query. Regards.