ketamine hydrochloride has 2 distinct synonyms spread across 1 of its 1 sense. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. WordNet records no antonym for it — antonymy is a relation between word forms rather than concepts, so it is deliberately sparse.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a general anesthetic and tranquilizer (not a barbiturate) that is administered intravenously or intramuscularly; used mainly by veterinarians or for minor surgery with geriatric or pediatric patients; taken in large doses it causes hallucinations similar to those associated with the use of PCP
Synonyms, antonyms and the broader and narrower relations for ketamine hydrochloride come from Princeton University’s WordNet. Full sources and licences.