Capsule
A capsule was a pill in the form of a small rounded gelatinous container with medicine inside.

In 2269, while Nurse Chapel and Harry Mudd were discussing the love potion and using the love potion crystal on Spock, Chapel thought that she would just break the capsule and rub it on her skin, and then touch Spock, so she broke the capsule between her hands. ()

This medicine was mentioned in a detective novel Data was reading in early 2364 to become more prepared for a Dixon Hill adventure. ()

A capsule was also the part of a 1960s rocket where it was the only place Humans on the ship could be without dying.

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Medicine