The vapor is so irritating that a person will seek to leave a contaminated area. Because this warning causes the person exposed to take immediate steps to decontaminate, the Lewisite lesion will probably not be as severe as a mustard lesion. Immediate decontamination and treatment of lesions. A specific antidote, BritishAnti-Lewisite, decreases systemic effects but causes some toxicity itself. Persistence is 24 hours to one week.
Phosgene oxime is an itchingstinging agent that causes a corrosive skin and tissue lesion.
The vapor is extremely irritating, and both vapor and liquid cause almost immediate tissue damage. The mechanism by which phosgene oxime causes biological effects is unknown. On the skin and all mucous membranes, CX liquid or vapor causes immediate pain on contact. Extreme pain may persist for days. It is irritating and painful to the eyes and upper airways.