I've been on an SNRI for a bit now, specifically a synthetic metabolite variant. Surprisingly, for me, it has both an emotional feeling and a perceived physical sensation.

For the emotional, it's kinda like wearing a climbing harness with a trustworthy belayer. Sure, sometimes life throws a bit of a curveball, causing me to lose my emotional purchase but, most of the time, it keeps me from falling into depressive thinking patterns. More recently I had some pretty rough stuff happen in my life, to put it lightly, that took me to to some pretty places but, I my little chemical belayer caught me before I went splat on the rocks and helped me to get out of the funk.

For the perceived sensation, it's a bit hard to describe. At times throughout the day, I feel a sensation that is kinda like a tingling on the inside of my skull. It's a bit weird but much better than brain zaps.