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WHO naming stem · suffix · 82 listed names

-onium

quaternary ammonium compounds

WHO's definition, quoted as written in the 2024 stem book
Names only. This page is about -onium as a part of a name. It has nothing on uses, doses, side effects or interactions of any medicine that carries it, and nothing here is medical advice. Ask a pharmacist or doctor about the medicine itself.

Where it sits in a name

WHO writes the stem as -onium. So the letters onium sit at the end of the name (…onium).

All 82 names WHO lists under -onium

These are the INN in group (a) of Part IV of the stem book: names in which WHO says the stem is used as defined. The stem is marked where WHO places it. A-Z as WHO lists them.

  1. aclatonium napadisilate
  2. alcuronium chloride
  3. ambenonium chloride
  4. azamethonium bromide
  5. benzalkonium chloride
  6. benzethonium chloride
  7. benzilonium bromide
  8. benzopyrronium bromide
  9. benzoxonium chloride
  10. bevonium metilsulfate
  11. candocuronium iodide
  12. carpronium chloride
  13. cefalonium
  14. cetalkonium chloride
  15. cethexonium chloride
  16. cetrimonium bromide
  17. ciclonium bromide
  18. cyclopyrronium bromide
  19. dacuronium bromide
  20. decamethonium bromide
  21. deditonium bromide
  22. denatonium benzoate
  23. diponium bromide
  24. disiquonium chloride
  25. dodeclonium bromide
  26. dotefonium bromide
  27. emepronium bromide
  28. fenclexonium metilsulfate
  29. fentonium bromide
  30. fludazonium chloride
  31. fubrogonium iodide
  32. furtrethonium iodide
  33. glycopyrronium bromide
  34. heteronium bromide
  35. hexafluronium bromide
  36. hexamethonium bromide
  37. hexasonium iodide
  38. hexopyrronium bromide
  39. lauralkonium chloride
  40. mebezonium iodide
  41. mecetronium etilsulfate
  42. metalkonium chloride
  43. methylbenzethonium chloride
  44. miristalkonium chloride
  45. octafonium chloride
  46. opratonium iodide
  47. otilonium bromide
  48. oxitefonium bromide
  49. oxydipentonium chloride
  50. oxyphenonium bromide
  51. oxypyrronium bromide
  52. oxysonium iodide
  53. pancuronium bromide
  54. penoctonium bromide
  55. pentamethonium bromide
  56. pentolonium tartrate
  57. pipecuronium bromide
  58. pirralkonium bromide
  59. polidronium chloride
  60. polixetonium chloride
  61. prodeconium bromide
  62. prolonium iodide
  63. rapacuronium bromide
  64. ritropirronium bromide
  65. rocuronium bromide
  66. sepazonium chloride
  67. sofpironium bromide
  68. stercuronium iodide
  69. stilonium iodide
  70. sultroponium
  71. suxamethonium chloride
  72. suxethonium chloride
  73. tetradonium bromide
  74. tetrylammonium bromide
  75. tiametonium iodide
  76. tibezonium iodide
  77. tiemonium iodide
  78. tiodonium chloride
  79. toloconium metilsulfate
  80. tonzonium bromide
  81. triclobisonium chloride
  82. vecuronium bromide

Decode another name

Decoded

cefalonium

Listed INNCarries 3 WHO stems, most specific first: -onium

  • -oniumend of the nameWHO lists it hereWHO definition: quaternary ammonium compounds
  • -iumend of the nameWHO lists it hereWHO definition: quaternary ammonium compounds
  • cef-start of the nameWHO lists it hereWHO definition: antibiotics, cefalosporanic acid derivatives

“cefalonium” is an INN that WHO lists under -onium, -ium, cef- in the 2024 stem book.

The same decoder as the front page: it reads the letters of a name against all 482 WHO stems, in your browser.

Source and licence

The definition of -onium (Part II B) and the 82 names (Part IV, group (a)) are from Use of stems in the selection of International Nonproprietary Names (INN) for pharmaceutical substances, 2024 (World Health Organization, Stem book 2024 (ISBN 978-92-4-009938-8); covers proposed INN Lists 1-129). Checked .

Adapted from: Use of stems in the selection of International Nonproprietary Names (INN) for pharmaceutical substances, 2024. Geneva: World Health Organization; 2024. Licence: CC BY-NC-SA 3.0 IGO. This adaptation was not created by WHO; WHO is not responsible for its content or accuracy and does not endorse this site. The data file stems.json is shared under the same licence.