Resources for Health Professionals


The allergic reaction to penetrating cercariae is self-limiting; signs and symptoms usually will resolve within 1-2 weeks. Minimal symptomatic treatment and good hygiene to prevent itching and secondary infections are usually sufficient treatment for most cases of cercarial dermatitis.

Treatment of cercarial dermatitis has not been evaluated in clinical trials. Systemic antihistamines or topical antihistamines or corticosteroids can be used to reduce symptoms. Topical antiseptics or antibiotics as well as systemic antibiotics may be needed in the case of secondary infection.


  • Caumes E, Felder-Moinet S, Couzigou C, Darras-Joly C, Latour P, Léger N.. Failure of an ointment based on IR3535 (ethyl butylacetylaminopropionate) to prevent an outbreak of cercarial dermatitis during swimming races across Lake Annecy, France. Annals Trop Med Parasitol 2003:97:157-63.
  • Chamot E, Toscani L, Rougemont A. Public health importance and risk factors for cercarial dermatitis associated with swimming in Lake Leman at Geneva, Switzerland. Epidemiol Infect 1998:120:305-4.
  • Hoeffler DF. “Swimmers’ itch” (cercarial dermatitis). Cutis 1977;19:461-7.
Page last reviewed: May 26, 2020