Absorption of vitamin D at dietary amounts decreased after
ezetimibe use in experiments with rodents and in vitro [15]. In this
randomized, double-blind, placebo-controlled trial, despite a good
drug adherence during more than five half-lives of ezetimibe, the
same effect was not replicated with a single 50,000 IU cholecalciferol
dose.
We cannot know whether similarresultswould have been observed
had we used smaller daily doses of vitamin D3. Nevertheless, a prior
study also demonstrated no difference in the serum concentrations of
lipid-soluble vitamins in patients with primary hypercholesterolemia
after 12 weeks of ezetimibe 10 mg/day [27], which suggests that
ezetimibe does not impair dietary vitamin D absorption.
Although the interest in the effects of ezetimibe on serum 25OHD
levels in humans has been rising lately, data concerning this topic re-
mains scarce. A recent study with hypercholesterolemic patients
showed that the administration of simvastatin/ezetimibe 10/10 mg
was associated with less than one half of the increase in 25OHD levels
seen with the simvastatin 40 mg, for similar low-density lipoprotein
cholesterol lowering [28]. Since the mechanisms which mediate
statins raise in 25OHD levels are not clearly elucidated, the amount of
simvastatin administered was lower in the association of simvastatin/
ezetimibe and there was no group receiving monotherapy with
ezetimibe,it is not possible todetermineif those results could be attrib-
uted to a dose dependent effect of simvastatin or to a decline of vitamin
D intestinal absorption by ezetimibe