If loopdoend’s doing this, it feels like a good bet that there’s a doctor in the mix judging that it’s medically appropriate for them.
Suppose you’re immunocompromised. Wouldn’t it be worth the diarrhea to avoid infections your body couldn’t fight off?
Suppose you’re in a situation where you’re having lots of opportunities for infection. Whether you can or can’t control that situation, the end result is the same: you know your body is going to be challenged by infectious disease frequently in a way that most people’s bodies aren’t. Isn’t it plausible that the infectious agent may have less opportunity to evolve if you didn’t contract it as frequently?
Different forms of therapy might be both individually and collectively optimal for people in different situations. What’s right for a person who isn’t at risk isn’t the same as what’s right for a person who is at risk.
The overuse of antibiotics is mostly in farm animals, which represent 73% of global antibiotics use, and 90% of American antibiotics use.
Preventatively using antibiotics is a horrible idea, for one it increases the risk of creating resisitant strains, and we are already running out of antibiotics (especially broadband ones). Moreover, antibiotics in general are known to mess with you gut biome whose importance we are just beginning to understand (we know it plays a role in many physical and mental illnesses for example). Then there are the side effects which for doxycyline include diarrhea, increased risk of bowel cancer, higher sensitivity to the sun (and associated risk of skin cancer).