While you technically can flush your old pills or throw them out, the The Pharmacy Guild of Australia strongly advises against it. That and there's enough nasty stuff going into sewage that it's best to keep medicine out of there if you can.
Photo: Jim Crocker
When you flush the toilet, that water and its contents have to go somewhere. In many locations, it goes to a wastewater treatment plant and then gets dumped into a nearby body of water. That means whatever makes it through treatment ends up in the environment and, eventually, back into our drinking water.
So far, scientists don't have conclusive evidence that flushed drugs are harming human health (probably not, since they're so diluted) or a good handle on what's happening in the environment — how the drugs affect fish, for example. Don't forget that the drugs you do take also end up in wastewater: what goes through your body eventually gets flushed.
In most cases your body breaks the drug down into different chemicals — but not always, and sometimes those smaller chemicals are potentially active as well.
Fortunately, wastewater treatment removes some pharmaceuticals. Depending on the drug, some studies find that 95 per cent of it is removed; others say only half. It turns out to be difficult to study the effects of pharmaceuticals in water in the environment, because there are so many different drugs to look for, and they are so diluted that their effects may be subtle.
Where to Dump Your Drugs Instead
The rubbish is a popular option, but two issues remain: people may find your drugs in the trash and drugs in landfills can also potentially affect the environment. For that reason, the packaging on fentanyl patches instructs you to flush them; you wouldn't want your pet or toddler getting a dose of the medication if they find it in the rubbish.
Really, your options depend on how important it is to get the drug out of your house right away. For most drugs, it's best to bring them to a drug disposal location or event at your convenience.
Failing that, unneeded or expired drugs can simply be returned to your nearest pharmacy, according to NPS MedicineWise.