Choc'pa

Choc'pa is a substance that is poisonous to a number of humanoid species, including both Klingons and humans.

After Gerda and Idun Asmund's adoptive Klingon uncle Lenoch was stabbed to death during a feud with a rival clan, their adoptive father discovered that the knife used to stab Lenoch had been coated in Choc'pa.

Later, in his campaign of vengeance against his former USS Stargazer (NCC-2893) crewmates, Doctor Carter Greyhorse stabbed Gilaad Ben Zoma with Idun Asmund's knife, which he also had coated in Choc'pa. After Greyhorse had been uncovered as the murderer, Idun remembered what her adoptive father had done after Lenoch's death, and told Doctor Beverly Crusher that the dying Ben Zoma had likely been poisoned. She suggested that Crusher apply the antidote for Choc'pa. This was successful, and Ben Zoma soon recovered from his wounds.