Hi there the lidocaine is in magic mouthwash.. Does he have a tooth or something that is irritating his tongue? I find that happens with me occasionally - is it a sore or a reddened area - I know talking when it's painful just aggravates it. When I have a sore tongue day (or two!) I switch to soothing cool creamy ish type foods to help my tongue recuperate - I also am careful about which side I sleep on sleeping with the sore area pressing up against something isn't helpful. And having an ibuprofen will help with pain and inflammation. When I'm having a particularly bad sore tongue day I do go back to the manuka for a few days... But do keep a close eye on it... And show it to a different doc. Good luck!