You don't have to worry about the medicines showing up in your drinking water. State laws mandate the purity of your drinking water and all drinking water, i.e., purification treatment plants, are required to have their water tested on a regular basis. They have to remove herbicides, pestisides, fertilizers, toxins from decomposing dead animals,overflos from plants, things that make medicines pale by comparisons. The hardest thing to remove happens to be types of protozoa, and they will make people the sickest. But the chemicals from medicines are removed also. Chemicals are added to the water which will precipitate the other chemicals - not a difficult process. My husband was an engineer in one of the treatment plants in Texas and I'm sure other states' laws provide for water that is as safe as the water in Texas.