A 16-year-old girl was seriously stung on her abdomen by a jellyfish as she jumped on her small surfboard. She and her mother identified the animal from photographs as Chrysaora fuscescens. Within several minutes the girl developed a massive abdominal cutaneous eruption composed of hundreds of punctuate erythematous papules and macules, which persisted for 5 to 7 days. Persistent urinary incontinence and biliary dyskinesia appeared over the following night. It is theorized that a systemic uptake of venom occurred percutaneously after contact of the jellyfish tentacles with her abdominal skin. The result was an injury to the urinary and biliary bladders. This is the first case report of such sequellae after topical contact with a marine animal. The causal relationship of these abnormalities with the sting is suggested by their temporal association. The gallbladder disorder required surgical intervention, but spontaneous resolution of the urinary bladder dysfunction occurred within 20 months.