Tick-borne illnesses are being reported increasingly often. Unlike Lyme disease, which tends to be indolent, Rocky Mountain spotted fever and ehrlichiosis can kill and so must be recognized and treated promptly. These diseases require clinical diagnosis, because laboratory confirmation with antibody tests takes too long. Tetracycline hydrochloride, doxycycline (Doryx, Vibramycin), or chloramphenicol (Chloromycetin) treatment is effective. Other diseases (eg, babesiosis, tularemia) are encountered occasionally and can also be fatal but are treatable with antibiotics.