For people who I know also struggle with weight, and who I feel comfortable with, I will outright tell them that I’m taking a medication that helps with weight loss. If they ask for the name, I tell them. As you allude to, weight struggles are absolutely horrible, especially in our society which correlates your body size with your morality, and I am staunchly against gatekeeping something that works for me when it could help someone else, too.

For people like random work acquaintances, I agree with the approach that another commenter mentioned, saying something along the lines of, “I’m on a medication that has affected my appetite.”