How much vision does he have? Can he see bright patches of color if he moves it around (like to peripheral vision or where he detects some light, etc.) so you can wrap the bottles with neon-colored stickers (having made note of the pharmacy instructions, or use an old empty bottle) and color code the neon. Orange for one pill, yellow for another, green for yet another?

This page has bright labels of various sorts and if you bought full sheet labels so you can cut them to size, that would be a starting place.

Does that help? There are also lots of gimmicks for using electronic tags with smart phone so you can detect them when they go missing. Put tags on the bottles, keys, etc.

SRS