Eagle effect

The Eagle effect, Eagle phenomenon, or paradoxical zone phenomenon, named after Harry Eagle who first described it, originally referred to the paradoxically reduced antibacterial effect of penicillin at high doses,[1][2] though recent usage generally refers to the relative lack of efficacy of beta lactam antibacterial drugs on infections having large numbers of bacteria.[3] The former effect is paradoxical because the effectiveness of an antibiotic generally rises with increasing drug concentration.

  1. ^ Eagle, Harry; Musselman, A. D. (July 1948). "The rate of bactericidal action of penicillin in vitro as a function of its concentration, and its paradoxically reduced activity at high concentrations against certain organisms". The Journal of Experimental Medicine. 88 (1): 99–131. doi:10.1084/jem.88.1.99. PMC 2135799. PMID 18871882.
  2. ^ Yourassowsky, E; Vander Linden, MP; Lismont, MJ; Schoutens, E (1978). "Qualitative study of paradoxical zone phenomenon of penicillins against 17 bacterial species of clinical importance". Chemotherapy. 24 (2): 92–6. doi:10.1159/000237766. PMID 340171.
  3. ^ Stevens, DL; Gibbons, AE; Bergstrom, R; Winn, V (July 1988). "The Eagle effect revisited: efficacy of clindamycin, erythromycin, and penicillin in the treatment of streptococcal myositis". The Journal of Infectious Diseases. 158 (1): 23–8. doi:10.1093/infdis/158.1.23. PMID 3292661.