Hi.. Thanks for writing to us.. It looks like there is a severe dry mouth and thick feeling of tongue is also due to dryness and inflammation. Rough spot on inner lip can be due sticking and rubbing of the teeth to the inner lip leading to tear in mucosa and causing inflammation and ulceration.. There can be a number of causes for dry mouth like severe dehydration, salivary gland disorders, if you take any medication then it can be a side effect of it, Sjogren s syndrome etc.. I would suggest you to get a clinical examination done by an oral physician so that the exact cause of dry mouth can be ruled out. Treating the underlying cause will help in relieving the symptoms.. For relieving the symptoms now you should chew sugar free chewing gum and suck lemon drops as they stimulate salivary glands to produce more saliva.. You can start gargling with Methyl cellulose containing mouthwash like Biotene as they are helpful in reducing dryness in mouth.. You can also use xylitol containing oral mucosal patches as they can lubricate the inside of mouth.. Use artificial saliva drops can help in reducing dry mouth.. Hope your query is resolved.. Regards.