prophylaxis
noun
pro·phy·lax·is
ˌprō-fə-ˈlak-səs 
also ˌprä-
plural prophylaxes
ˌprō-fə-ˈlak-ˌsēz
also ˌprä-
: measures designed to preserve health (as of an individual or of society) and prevent the spread of disease
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In Greek, phylax means "guard", so prophylactic measures guard against disease by taking action ahead of time. Thus, for example, before the polio vaccine became available, prophylaxis against polio included avoiding crowds and public swimming pools. These days a well-known kind of prophylactic is used to prevent sexually transmitted diseases; but prophylactic measures only work when people use them.
Examples of prophylaxis in a Sentence
Recent Examples on the Web
The subsequent approval of the HIV-prevention pill — called pre-exposure prophylaxis, or PrEP — in 2012 only hastened the decline.
—
Benjamin Ryan, NBC News, 12 Nov. 2024
The latter option, called PEP, for post-exposure prophylaxis, has to be started within 72 hours of exposure to be effective.
—Keren Landman, Vox, 7 Dec. 2018
Similar algorithms have been developed in Kenya and Uganda to help determine ideal candidates for pre-exposure prophylaxis (PrEP).
—Jennifer Lotito, Forbes, 3 Oct. 2024
After infusion, 94% of patients in a trial no longer needed routine prophylaxis therapy.
—Web Golinkin, Forbes, 12 Sep. 2024
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Benjamin Ryan, NBC News, 12 Nov. 2024
The latter option, called PEP, for post-exposure prophylaxis, has to be started within 72 hours of exposure to be effective.
—Keren Landman, Vox, 7 Dec. 2018
Similar algorithms have been developed in Kenya and Uganda to help determine ideal candidates for pre-exposure prophylaxis (PrEP).
—Jennifer Lotito, Forbes, 3 Oct. 2024
After infusion, 94% of patients in a trial no longer needed routine prophylaxis therapy.
—Web Golinkin, Forbes, 12 Sep. 2024
See all Example Sentences for prophylaxis
Dictionary Entries Near prophylaxis
Cite this Entry
“Prophylaxis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prophylaxis. Accessed 30 Nov. 2024.
Copy CitationMedical Definition
prophylaxis
noun
pro·phy·lax·is
-ˈlak-səs
plural prophylaxes
-ˈlak-ˌsēz
: measures designed to preserve health and prevent the spread of disease : protective or preventive treatment
prophylaxis against viral diseases
a paste containing fluorine for dental prophylaxis
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