Death results from respiratory failure, hypoxemia, hypovolemia, or a combination of these factors. Hypoxia and hypotension may progress particularly rapidly and suggest a poor prognosis. Complications include infection of damaged lungs and delayed deaths following such respiratory infections. Riot control agents produce a burning sensation predominantly in the eyes and upper airways. This irritation is typically more intense than that caused by phosgene and is unaccompanied by the distinctive odor of phosgene.
Nerve agents induce the production of watery secretions as well as respiratory distress.
However, their other characteristic effects distinguish nerve agent toxicity from organohalide inhalational injury. The respiratory toxicity associated with vesicants is usually delayed but predominantly affects the central rather than the peripheral airways. Vesicant inhalation severe enough to cause dyspnea typically causes signs of airway necrosis, often with pseudomembrane formation and partial or complete upper airway obstruction. Finally, pulmonary parenchymal damage following vesicant exposure usually manifests itself as hemorrhage rather than pulmonary edema. Peak expiratory flow rate may decrease early after a massive phosgene exposure.