Willow bark contains salicylic acid, but aspirin is SYNTHETIC salicylic.

Salicylic acid is the compound found in willow bark. In that form, it's extremely irritating to our digestive tracts. Aspirin is acetylsalicylic acid, which is not nearly as irritating, and later metabolizes to salicylic acid. It's a much better way to deliver the drug.

All aspirin is made in the lab. However, it does break down readily into vinegar and a couple of other simple compounds so if it's out of date, flush it.

As for flushing other medication, it's still the preferred way to get rid of it because sending it to a landfill keeps it in concentrated form while flushing it disperses it.

I wish there were better options for disposal, myself, such as returning it to manufacturers for reclaimation. Unfortunately, flushing is the best we've got now.

I was just being lazy and wanted to get rid of the old aspirin. I have a box of old pills to go take, when it is full. maybe it is because they use to manufacture drugs here, but that is going to china like all the rest now.