Vinnie picking up an empty bag of Amon Rush.
Amon Rush is the eponymous drug of Sift Heads Rush.
Sift Heads Rush[]
One of many enemies under the influence of Amon Rush. Note the yellow health bar.
Having ensured that Vinnie is put behind bars, Luzio goes back to business. His goal is to flood Chicago with the new drug called Amon Rush. According to various intel encountered by Vinnie, it is a seriously addictive drug which causes people to act crazy and makes them immune to pain.
Amon Rush can be distinguished in-universe by the yellow colour (exclusive to the bags the drug is packed in). While investigating various places in Chicago, Vinnie encounters enemies who are, presumably, drugged with Amon Rush. If not taken down soon enough, they replenish their health. The enemies which are under the drug's influence at times say non-sequitur lines, stating, for example, that they will not come back. It is an indication that they are hallucinating. Presumably, as Vinnie and Kiro dispose of Luzio and Shigeru's partner and the police arrives at Dock 28, further deliveries of Amon Rush are prevented.