[Schatze]

Many prescription pill bottle contains the size, style of pill (capsule, pill, caplet), color, and indentation, as well as the letters imprinted.

If it doesn't, it carries a number that can be used to look up what the pills are supposed to look like.

Not that it's not an almost foolproof method, but I wouldn't do it if your name causes you to be regularly flagged for the "butt pucker" level of screening.