If you have RBF, your doctor can give you antibiotics that are highly effective at curing the disease. Penicillin is the antibiotic most often used. If you are allergic to penicillin, your doctor can give you other antibiotics. Without treatment, RBF can be serious or potentially fatal. Severe illnesses can include: Infections involving the heart (endocarditis, myocarditis, or pericarditis); Infections involving the brain (meningitis); Infections involving the lungs (pneumonia) and Abscesses in internal organs. While death from RBF is rare, it can occur if it goes untreated.