The world’s largest company is taking a unique approach to dealing with the opioid crisis.

ABC News reports that Walmart pharmacies in the US will provide DisposeRX packets free with opioid prescriptions. If the patient has leftover medication, they just pour the powder in the bottle with the meds, add warm water and shake. The pills are then turned into a useless, biodegradable gel. Check it out in the video below.

Walmart customers can request a free packet anytime, and people with long-term prescriptions will get one every six months.

It’s a smart idea, one that can prevent unused medications from entering the black market. And thankfully, the resulting gel isn’t brightly colored. We all know how THAT goes.