Objective: To report 3 cases of nephrogenic systemic fibrosis (NSF) focussing on the time course of clinical symptoms after exposure to gadolinium based contrast agents (GBCA) and to discuss pharmacokinetic aspects of commercially available GBCA. Patients' details: All 3 patients (2 men, 1 woman, aged 51-54 years) suffered from end-stage renal disease (ESRD) and were on long-term dialysis. Linear GBCA compounds were given to all patients and NSF symptoms started 6 months, 1 and 4 years after the last GBCA exposure. In 2 patients, GBCA was administered after the occurrence of (unrecognized) NSF symptoms leading to worsening of clinical courses. 1 of the patients received multiple therapies (e.g. UV-A1 treatment, physical therapy) without significant improvement, 2 patients died from cardiac complications shortly after the diagnosis of NSF. Conclusion: NSF may develop after a longer period of time than generally reported and GBCA administration may aggravate or accelerate chronic, subclinical NSF symptoms. © 2009 Dustri-Verlag Dr. K. Feistle.