Oral versus intramuscular phytomenadione - Safety and efficacy compared

Oral and intramuscular phytomenadione (vitamin K1) prophylaxis became an is sue following the report of a potential carcinogenic effect of intramuscula r but not oral phytomenadione prophylaxis. There is increasing evidence, ho wever, that oral phytomenadione prophylaxis is less effective for the preve ntion of late vitamin K deficiency bleeding (VKDB) than intramuscular proph ylaxis. Following a report of an increased cancer risk after intramuscular phytomen adione, a series of papers on this issue appeared. Although an increased ri sk for solid rumours could almost certainly be excluded, a potential risk f or acute lymphatic leukaemia in childhood could not be ruled out definitive ly. Almost all cases of late VKDB are preventable with intramuscular phytomenad ione prophylaxis administered once at birth, whereas a single oral dose giv en at birth is much less effective. Repeated oral phytomenadione doses give n to breast-fed infants either weekly (1mg) or daily (25 mu g) seem to be a s effective as intramuscular phytomenadione prophylaxis. The efficacy of 3 oral 2mg doses with the new mixed micellar preparation ('Konakion MM') rema ins to be established. Although a number of studies have failed to confirm a cancer risk with phyt omenadione, these studies have been unable to rule out a risk definitely be cause absence of evidence is not evidence of absence. A meta-analysis of th e available studies might provide 95% confidence intervals narrow enough to exclude even a small cancer risk with some certainty. Oral prophylaxis wil l probably be as safe as the intramuscular prophylaxis if given daily (25 m u g) or weekly (1mg).