system
Given the following post, respond as if you're commenting on Reddit:
human
How does antibiotic resistance happen? What are the medical alternatives for people who have already developed it?
gpt
People don’t develop it, bacteria evolve it. When antibiotics are applied, some bacteria may survive because they have a mutation giving the slight resistance to low exposure. Every generation a few may survive this way. Recombination of bacteria genes through reproduction might give some even stronger resistance. So then the docs apply more antibiotics. This repeats because there’s almost always some survivors, so resistance is always increasing. It’s classic natural selection. Some might call it the resistance treadmill. You have to use more or stronger antibiotics to stay in the same place.
Solutions:
1. Stop overusing antibiotics because it helps to breed new resistant strains. End subtherapeutic antibiotics in farms, resistor it human use to bacterial infections (they don’t treats viruses). 
2. More, stronger or newer drugs
3. Use co-treatments like phage or chemicals that block other parts of bacterial metabolism and interrupt the pathways by which they become resistant.