Hello we have just started our 8 week old on Losec from Zantac and he seems worse not better. Zantac usually takes around 2 hours to work. Can anyone tell me if Losec is the same or does it take a few days? He seems to have difficulties in keeping the Losec down when he didnt have any problems with Zantac. This has nothing to do with the taste but his reflux as he is vomiting it back up in a few mins time.