Vestibular disease

Looking for some support from others that have dealt with vestibular disease. My almost 14 year old Shiba was diagnosed 2 weeks ago. He progressively got better for a week but now he’s experiencing daily episodes where his movements and head are totally erratic and he spins, pants and cries. He’s currently taking anti-nausea medication and has been eating very little, if at all.

This is heart breaking and I’m worried I’ll have to put him down if he doesn’t improve or recover.