The parent compounds of acetaminophen (US market in 1955 in the US as Tylenol and other products) were first discovered in 1886 (acetanilide) and 1887 (phenacetin). These were the earliest synthetic fever Taking Tylenol? The Glutathione Connection Dr. Green Mom Data summary: IL 4 regulates glutathione levels in the liver and lung Download Scientific Diagram The FDA is signaling that perhaps immediate treatment with acetaminophen is less clearly needed for a low grade fever, especially in pregnancy, unless theres a stronger indication for it., Safer