How long does Vicodin stay in your system? Vicodin contains acetaminophen and hydrocodone to relieve pain. The effects of Vicodin last around 4 hours, traces of the drug can remain in your system for up to 72 hours. After a severe injury or intense surgery, your doctor may prescribe a narcotic painkiller known as Vicodin. Buy Vicodin Online because it is effective in providing quick relief from pain.