A drug drop-off site
A city may have medicine drop-off sites, such as at some pharmacies.
If no drop-off site is available, consider throwing the medicine (in its container) into the regular trash. Hopefully, the medicine will stay in its container in the local landfill for hundreds of years. If a medication is dumped outdoors or flushed down the toilet, it may end up in our lakes, streams, drinking water, and fish.