O n a threadbare carpet in the living room of a Bernal Heights bungalow, I lay blindfolded on my back. Two middle-aged rescue terriers, one missing an eye, sniffed my feet and climbed up and down my legs. F**kin’ Perfect by Pink blared in the background, but the music sounded muffled and distant, like I was listening from underwater. It was 1pm on a Thursday. Instead of going to the office, I’d allowed a shaman named Jonathan to inject my thigh muscle with a large dose of liquid ketamine. Even in my compromised state, high and spread out like a corpse on a stranger’s rug, I knew I’d reached peak absurdity. I also knew I wouldn’t emerge from this activity with even a slight improvement to my mental health. Jonathan was a kind man who had studied psychedelic medicine under the tutelage of respected practitioners. He’d helped many of my friends address deep-seated issues in remarkable ways. But my friends weren’t suffering from suicidal, treatment-resistant depression .…