Antifungal properties of 5-hydroxytryptamine (serotonin) against Candida species in vitro

J Med Microbiol. 2003 Feb;52(Pt 2):169-171. doi: 10.1099/jmm.0.04987-0.


In this study the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of 5-hydroxytryptamine (5 HT, serotonin) against clinical isolates of Candida albicans (n = 11), Candida glabrata (n = 9), Candida tropicalis (n = 10) and Candida parapsilosis (ATCC 22019) using a broth microdilution test were investigated. In addition, it was examined whether delayed regrowth as a post-antifungal effect results following short exposure to 5 HT. 5 HT showed antifungal activity towards all isolates of Candida spp. The isolates yielded comparable MIC and MFC values of 5 HT in the range 0.91-7.34 mM and 1.83-14.68 mM, respectively. A lag in regrowth was dependent on the concentration tested. Treatment for 3 h at concentrations of 5 HT below and equipotent to the MFC resulted in a delayed regrowth of 8-12 h for isolates of Candida spp. In conclusion, these in vitro studies clearly demonstrate antifungal effects of 5 HT. Identifying the mode of action could be of great help in developing and researching new antifungal drugs.

MeSH terms

  • Antifungal Agents / pharmacology*
  • Candida / drug effects*
  • Candida / growth & development
  • Candida albicans / drug effects
  • Candida albicans / growth & development
  • Colony Count, Microbial
  • Dose-Response Relationship, Drug
  • Free Radical Scavengers
  • Humans
  • Microbial Sensitivity Tests
  • Serotonin / pharmacology*
  • Time Factors


  • Antifungal Agents
  • Free Radical Scavengers
  • Serotonin