Ma'anar ƙamus na kalmar "anesthetic agent" wani abu ne da ake amfani da shi don haifar da maganin sa barci, yanayin da majiyyaci ya kasance a cikin sume ko rasa jin dadi a wani sashe na jiki yayin aikin likita. Ana iya gudanar da magungunan anesthetics ta hanyar numfashi, allura, ko aikace-aikacen waje, kuma suna aiki ta hanyar toshe siginar jijiya a cikin jiki don katse jin zafi da sani na ɗan lokaci. Misalai na yau da kullun na magungunan kashe qwari sun haɗa da nitrous oxide, propofol, da lidocaine.