Necrobacillosis, often used synonymously with Lemierre's syndrome, is a form of abscess infection in the peritonsillar area associated with a thrombophlebitis and caused by the strict anaerobic species Fusobacterium necrophorum. The thrombosis formed affects the internal jugular vein, from which the bacteria are seeded out in the bloodstream and cause bacteremia. Septicemia is a common complication with an often fatal outcome. Necrobacillosis is very rare and is referred to as the 'forgotten disease'. It is probably frequently overlooked in clinical practice in its early and milder forms such as tonsillitis (sore throat) and peritonsillar abscess. F. necrophorum frequently participates in these infections and is thus suspected to have an etiological role in Lemierre's syndrome. Similarly, F. necrophorum seems to play an important role in noma (cancrum oris) and this disease is also included in the necrobacillosis complex. Diagnosis of infections of the necrobacillosis complex seeks to disclose F. necrophorum in swab samples or blood culture. The most commonly used therapy is metronidazole in combination with penicillin or amoxicillin. Clindamycin is also an option, especially in cases of penicillin allergy.