People often ask me whether I have side effects from taking Wegovy and I tell them yes, and that they are no joke: If you’re thinking of taking a weight-loss drug, you need to be prepared. Whoever I’m chatting to will stare expectantly, curious about the dark side of the Faustian bargain I—and over 8 million other Americans—have agreed to.

“The side effects are different for everyone, but for me,” I say, “I’m prettier, happier, more confident, my clothes look better, and more men take notice of me.”

I was never obese, or approaching it. I didn’t have diabetes, or prediabetes. A healthy weight range for someone of my height—which is 5'2″—is between 104 and 131 pounds. Sometime about a year ago, I’d simply edged into the upper part of that range. Then I saw an ad on the subway for a telehealth service that provides the drugs. I signed up on my phone, right on the train, clicking through the prompts about whether I was allergic to any medication, or if I was breastfeeding, blah blah blah, and then a week or so later a small package arrived with some lancets so I could draw a blood sample, which I did, sending it back to the company sealed in cardboard box. A few weeks later, I was popping the top off a pre-filled pen containing, among other chemicals, semaglutide, which would curb my appetite and make me feel full for longer when I did eat.

As I pressed it to my stomach—I hate needles—and heard and felt a click, I thought, What the hell am I doing? and This is absolutely insane. Flipped out, I went to sleep with panicked thoughts about fast-growing stomach cancers and allergic reactions racing through my mind. Then, I woke up without any appetite. In the two weeks that followed, I lost those stubborn eight pounds. While it happened, I didn’t feel jittery or on edge, or weak and starved. I felt like myself, just shrinking...