My Husband Is 63. He Is Experiencing Intermittent Dizziness, Vertigo,

My husband is 63. He is experiencing intermittent dizziness, vertigo, balance problems, has forceful vomit on 4 occasions recently. He has no headaches. He’s taking Trintellix and nasal ketamine for depression, tramadol, diltiazam, olmasartan, Clonazapam and vitamin supplements. He has a DBS unit implanted for his depression. I’m asking about the vomiting and vertigo related problems. He’s seen 2 ENTs and his ear crystals are fine. ?.