For me irritability has always been a major aspect of my TRD, but I didn’t feel any more irritable after my infusions, even the early ones. I did feel kind of dizzy and unsteady for a couple of hours and very lethargic for the rest of the day; I’d typically go home, have something to eat, then take a 3 - 4 hour nap. By the next morning I’d be feeling relatively normal, still a little slow and foggy maybe, but by evening the next day I’d be totally fine.
I hope the irritability after your infusions has passed and that you’re finding the treatments worthwhile and helpful. My sixth infusion was five days ago and I’m feeling better than I have in years; hopefully you’ll have similar success. I feel like my negative mental habits (ruminating, etc.) are much less powerful or compulsive or toxic, occur less often, and when I do notice them happening, I notice the occurrence more quickly and am more easily able to redirect myself to mindfulness or positive thinking.