My young Boxer girl (sorry, not a Yorkie) has been on Cytopoint since fall ‘19. Because of a breed predisposition to mast cells, traditional allergy meds are a last resort.
We have had zero problems with it. It has become much less effective over time, but that is most likely because there is food component (I need to do an elimination diet soon). To provide more relief we use off label dosing.
Aside from itching, she had severe axillary dermatitis. It looked like her armpits were going to rip.
Cytopoint was curative for this. She also had the white dog tear staining and crusty eye fur. It disappears for 1-2 weeks after injection.