The people responding to this seem to assume you’re doing so for funsies, which might be true. But that’s not what you said. So for their benefit, it’s worth pointing out that daily doxycycline is a pretty normal therapy for a range of chronic stuff—malaria prophylaxis, rosacea and skin that’s prone to infections, I’m sure there’s more.

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.