Old bunny with eating difficulties

Question
I have a 10 year old bunny who is having dental problems.  He was doing ok with regular cheek teeth filing but this is now not working.  He has one tooth missing so this grows too quick.  He laso has long cheek teeth roots.  He was last treated about four weeks ago and is due for another in a weeks time.  Since his last treatment he has the worst case of slobbers (he has been producing too much saliva for some time, but throught examined for problems swallowing to no avail), he jus sits with his head on the carpet and drools.  He has not been seen to eat hay for some time and is losing weight.  He can however eat pellets which he had in the past in very limeted supply before his currenty problems.  He is now rejecting veg after a couple of nibbles, unless it is banana.  Since I need him to keep eating I have been offering him pellets and critical care as often as he wants which he does eat.  He also has no control over his bladder and his bowels, but I thought this could be because he is eating more than he should pellet wise.  I have him on the highest fibre pellet I can find which he will eat as put him on one for digestion and it was too hard for him to eat or he didnt like it.  He is on metacam in case of pain at the highest dose possible.  He seems content but I just dont know what to do for the best.  Is he really content or am I just not facing facts.  He had blood test and he showed slight kidney damage but vet was not concerned with this as he has e-cuniculi which we control with routine panacur treatment once a year.  His weight is slowly going down.  He seems very alert when he is hungry even pawing my leg when he wants food but is quiet the rest of the time.  Do you have any suggestions to mention to my vet or any advice on feeding him which does not include just feed him hay as he wont eat this.  I am giving him herbs which he nibbles but not for long.  Many thanks

Answer
Dear Jenny,

This might sound like a strange idea, but if this were my bunny I would ask the vet about putting him on antibiotics.  In some cases, infection at the tooth roots may not be a full-blown abscess, but can cause enough inflammation and discomfort to cause drooling.  Keeping the bacterial population under control with antibiotics can help.

I know you don't have dual-acting penicillin available in the UK, but I would ask the vet about daily Penicillin-G Procaine injections, perhaps coupled with a long-acting fluoroquinolone, such as zeniquin/marbofloxacin.  At this point, it seems that it could not hurt to at least try this, and see if it gives him some relief.  

I hope this helps.

Dana