RT Journal
A1 LeBlanc ES, Perrin N, Johnson JD, Ballatore A, Hillier T
T1 Over-the-counter and compounded vitamin d: Is potency what we expect?
JF JAMA Internal Medicine
JO JAMA Internal Medicine
YR 2013
FD April 8
VO 173
IS 7
SP 585
OP 586
DO 10.1001/jamainternmed.2013.3812
UL http://dx.doi.org/10.1001/jamainternmed.2013.3812
AB 
Because vitamin D insufficiency can be harmful to health,1- 3 supplementation is often prescribed. However, the Food and Drug Administration (FDA) does not regulate vitamin D supplements, so potency may not be well evaluated. In a recent trial examining vitamin D in menopausal women, we found that compounded vitamin D3 (cholecalciferol) supplements varied significantly in potency. Only one-third of our compounded study pills met US Pharmacopeial (USP) Convention standards, which require that compounded pills contain 90% to 110% of the active ingredient.4 This variability in compounded cholecalciferol pills led us to additionally investigate over-the-counter (OTC) cholecalciferol pills, in which we also found variability.