Some medicines come in blister packs, so those might be able to be used by someone else.
[QUOTE=bordelond]
Is there anyway to check the unused medicine, pill by pill, for evidence of tampering? Pass the pills under a UV light or something? (Which would probably damage/neutralize some medicines, but still)
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Yes, I just saw something on the news about a machine that can analyze pills, while still in the bottle to make sure they are what they say they are. It’s designed to check for conterfeit pills, but I’m sure it would work for that.