Credé prophylaxis is the practice of washing a newborn's eyes with a 2% silver nitrate solution to protect against neonatal conjunctivitis caused by Neisseria gonorrhoeae, thereby preventing blindness.
[1] Between 1881 and 1883, Credé published three papers in Archiv für Gynäkologie, each titled "Die Verhütung der Augenentzündung der Neugeborenen" (Prevention of inflammatory eye disease in the newborn), describing his method and its results.
[1][note 1] The original procedure called for a 2% silver nitrate solution administered immediately after birth, as Credé erroneously believed that a 1% solution was ineffective due to a previous study by Hecker; however, this was eventually corrected and reduced back down to a 1% solution to reduce chemical irritation to the newborn's eyes.
[2] In the 1980s, silver nitrate was replaced by erythromycin and tetracycline treatments, which are better tolerated by the eye and more effective against Chlamydia trachomatis in addition to N.
[3] The works "Archiv für Gynäkologie" are freely available in the public domain.