Phenoxymethylpenicillin is more acid-stable than benzylpenicillin, which allows it to be given orally.[citation needed]
Phenoxymethylpenicillin is usually used only for the treatment of mild to moderate infections, and not for severe or deep-seated infections since absorption can be unpredictable. Except for the treatment or prevention of infection with Streptococcus pyogenes (which is uniformly sensitive to penicillin), therapy should be guided by bacteriological studies (including sensitivity tests) and by clinical response.[13] People treated initially with parenteral benzylpenicillin may continue treatment with phenoxymethylpenicillin by mouth once a satisfactory response has been obtained.[9]
The mechanism of phenoxymethylpenicillin is identical to that of all other penicillins. It exerts a bactericidal action against penicillin-sensitive microorganisms during the stage of active multiplication. It acts by inhibiting the biosynthesis of cell-wall peptidoglycan.[14]
The Austrian pharmaceutical company, Biochemie, was founded in Kundl in July 1946 at the site of a derelict brewery, at the suggestion of a French officer, Michel Rambaud (a chemist), who was able to obtain a small amount of Penicillium start culture from France. Contamination of the fermentation tanks was a persistent problem and in 1951, the company biologist, Ernst Brandl, attempted to solve this by adding phenoxyethanol to the tanks as an anti-bacterial disinfectant. This resulted unexpectedly in an increase in penicillin production: but, the penicillin produced was not benzylpenicillin, but phenoxymethylpenicillin. Phenoxyethanol was fermented to phenoxyacetic acid[16] in the tanks, which was then incorporated into penicillin via biosynthesis. Importantly, Brandl realised that phenoxymethylpenicillin is not destroyed by stomach acid and can therefore be given by mouth. Phenoxymethyl penicillin was originally discovered by Eli Lilly in 1948 as part of their efforts to study penicillin precursors, but was not further exploited, and there is no evidence that Lilly understood the significance of their discovery at the time.[5]: 119–121 [17]
There were four named penicillins at the time penicillin V was discovered (penicillins I, II, III, IV), however, Penicillin V was named "V" for Vertraulich (German for confidential);[5]: 121 it was not named for the Roman numeral "5".
Penicillin VK is the potassium salt of penicillin V (K is the chemical symbol for potassium).[citation needed]
^Hamilton R (2015). Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition. Jones & Bartlett Learning. p. 95. ISBN9781284057560.
^ abc"Penicillin V". The American Society of Health-System Pharmacists. Archived from the original on 20 December 2016. Retrieved 8 December 2016.
^ abcGreenwood D (2008). "Wonder Drugs". Antimicrobial Drugs: Chronicle of a Twentieth Century Medical Triumph. OUP Oxford. ISBN978-0-19-953484-5. Archived from the original on 20 December 2016.
^World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
^ abcSweetman S., ed. (2002). Martindale: The complete drug reference (Electronic version ed.). London: Royal Pharmaceutical Society of Great Britain and the Pharmaceutical Press.
^"Index (BP 2009)"(PDF). British Pharmacopoeia Commission Secretariat. Archived from the original(PDF) on 11 April 2009. Retrieved 26 March 2010.
^"Phenoxyacetic acid". PubChem. Bethesda, MD, USA: National Center for Biotechnology Information, National Library of Medicine. 26 December 2020. Retrieved 1 January 2021.
