How guinea pigs almost destroyed modern medicine

Description

Penicillin kills guinea pigs [1], so it’s a good thing we originally tested it in mice In May 1939, a team at Oxford injected 8 mice with Streptococcus bacteria. Half the mice were also given a shot of penicillin, and it’s only these that mice survived [2]. This test paved the way for human trials and the mass production of penicillin, which has since saved tens of millions of lives [3]. If guinea pigs had been used instead of mice, the penicillin could have killed them even without the bacterial infection, potentially halting research into its use in humans. So thank you mice, for not being guinea pigs. 1. Formal SB, Abrams GD, Schneider H, Laundy R. Penicillin in germ-free guinea pigs. Nature. 1963 May 18;198(4881):712-. 2. Gaynes R. The discovery of penicillin—new insights after more than 75 years of clinical use. Emerging infectious diseases. 2017 May;23(5):849. 3. Kardos N, Demain AL. Penicillin: the medicine with the greatest impact on therapeutic outcomes. Applied microbiology and biotechnology. 2011 Nov;92:677-87. It should be noted that toxicity is a function of dosage. Enough penicillin will also kill a mouse or a human. Penicillin is however lethal for guinea pigs at much lower doses than for mice.