Menadiol is an organic compound with the formula C<sub>6</sub>H<sub>4</sub>(COH)<sub>2</sub>(CH)(CH<sub>3</sub>). It is formally the p-hydroquinone derivative of 2-methylnaphthalene. The name vitamin K<sub>4</sub> can refer to:
Menadiol sodium diphosphate is approved in the UK for treatment and prevention of haemorrhage, mainly in obstructive jaundice (before and after surgery). Unlike natural, lipophilic forms of vitamin K, menadiol sodium diphosphate does not require bile for absorption, hence the use in obstructive jaundice. A disadvantage is that it takes 24 hours to show effects, though the effects do last for several days. It can cause hemolytic anemia, more commonly in people with glucose 6-phosphate dehydrogenase deficiency or vitamin E deficiency.
Menadiol is probably naturally produced by reduction of menadione ("vitamin K<sub>3</sub>"; see ) as an intermediate in the conversion from K<sub>3</sub> to MK-4. It can be oxidized in experimental conditions back to menadione.
<div class="skin-invert-image"></div>