Dear Sir, I am father of 4.5 years old celiac son. He is thin and weak but too active and brilliant. I have noticed from last few days he seems too dull, less active and often complaing for leg pains... perhaps becose of weakness and less eating... Sometimes he womit immidiately after taking meal..someone advised me for deworming and suggested Zental syrup. SHould i give him zental syrup and wht quantity should i give him?? pls advise..