Nembucaine

An effective anesthetic – on humans, anyway – Nembucaine was in use by the CIA and other intelligence agencies in the mid-1980s, frequently for unwanted and invasive surgical procedures on detainees. (“Torture” and “Prisoners” are such ugly words.)

Sadly, as Thomas Jerome Newton learned to his sorrow, Nembucaine is completely ineffective on natives of the planet Anthea. Not that he could ever convince his captors of that.

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Origin: The Man Who Fell to Earth by Walter Tevis.