John McKenna

Tetracyclines are called broad-spectrum antibiotics because they kill a broad range of microbes. Because of this they damage the gut flora, causing the overgrowth of Candida albicans, Staphylococcus spp. and Clostridium difficile. Liver and kidney damage can also occur with the use of these drugs, as can allergic reactions such as hives, skin rash and asthma.

1947 a newly discovered antibiotic called chloramphenicol was used in a clinical trial to treat an epidemic of typhus in Bolivia. Its success in curbing the epidemic led to its use in the treatment of typhoid fever, meningitis and brucellosis. At last scientists were discovering substances that could treat serious infections.

euphoria that surrounded the discovery of chloramphenicol was dampened somewhat when it was shown to have serious side effects. By 1950, many investigators had become alarmed by the mounting evidence linking it with serious blood disorders including anaemia and leukaemia.