N-acetylcysteine overdose is almost exclusively an iatrogenic event. This rare complication can lead to hemolysis or atypical hemolytic uremic syndrome. A 53-year-old Caucasian male accidentally received a two-fold N-acetylcysteine overdose that resulted in a presentation compatible with the atypical hemolytic uremic syndrome. The patient required temporary hemodialysis sessions, and he received treatment with eculizumab. This case report is the first reported N-acetylcysteine-induced atypical hemolytic uremic syndrome successfully treated with eculizumab. Clinicians should be aware of N-acetylcysteine overdose and its possible hemolytic complications.