Blister packs, just trim them down and paperclip a tiny type print out with all the usage, dosage and reaction stuff, along with a description.

Some things I repack in 2x2 or 2x3 zipper bags and label with a lumocolor pen. Others I repack in small vials that were origionally designed to carry toothpicks (actually, I think they might have first been centrifuge tubes) and tape a label on.