[cypher]

Mite treatment is actually quite toxic & should only be used after a skin scrape has shown a problem with mites, scratching van be due to lots of things & most often isn’t mites.
What substrate do you use & what do you feed him?
Do you use hay?
If his skin appears to be in poor condition or he has some fur loss try giving a pinch of flax seeds (linseed) & a drop of evening primrose oil daily.
Some hams do begin to show signs of ageing by about 18 months so it may just be that but I would definitely stop the mite treatment & make sure he’s getting all the nutrients he needs.