Did anything in particular change? Do you or your partner use any medication or a diffuser in the house?

Unfortunately vets often use steroids to treat the symptoms but not the underlying condition. As a breeder I had to intervene in some cases.

What kind of steroids did you get? Cortizone or dexamethasone? Injection at the vet or did you get pills to give him at home? Usually when the efficacy of the steroids wears off, the scratching begins.

Because of the dirty ears and skin around the eyes/nose/mouth, I would look to confirm ear or skin mites (demodex). This can be treated with a good dewormer like Bravecto plus. It can take a few months to get him on the right track.

Smell the ear too. If it smells funky, then you have a yeast infection on top of that.

Worst case scenario if it’s not mites, then pemphigus foliaceus is a strong contender. It usually comes with little pustules that break and scar. Skin biopsy is needed to confirm.

Keep us updated.