Background: Long-term investigations of persons exposed to mustard gas are few and have primarily focused on its carcinogenic properties. To our knowledge neuropathic pain has never been described. Objective: We investigated late symptoms in the skin after exposure to sulfur mustard. Methods: Five patients exposed to mustard gas during battlefield operations in the Middle East and five fishermen accidentally exposed to sulfur mustard by pulling shells leaking the chemical agent aboard their fishing vessels participated in this study. Clinical examination of the patients from the Middle East and telephone interviews with the fishermen were performed. Results: All patients suffered from neuropathic pain or other deafferentation symptoms. Conclusion: Persistent damage to the afferent nerve system resulting in chronic neuropathic symptoms is probably a frequent complication in persons exposed to mustard gas. (J Am Acad Dermatol 1998;39:187-90.)