At every RE visit I returned the used ones, they have biohazard containers
I took all my used meds and unused sterile waters to my RE's office and then to my OB's office for proper disposal. TAKE THEM IN A STURDY PLASTIC CONTAINER like those cheap new tupperware disposable containers and just hand them over.
It's riduculous that a hospital won't accept them. It's safer for them to dispose of them than you where any joe blow can get to them.