title: Vitamin D intoxication with severe hypercalcemia due to manufacturing and labeling errors of two dietary supplements made in the United States.
abstract: BACKGROUND
  More than 50% of Americans use dietary supplements, and 60-70% fail to report this use to their physicians. Intoxication from vitamin D supplements has been rarely reported but may now occur more frequently. This may be attributable to an increase in vitamin D supplement intake due to the findings that deficiency is common and has been associated with a number of disease states.
  
  
  OBJECTIVE
  We report two cases of vitamin D intoxication with dietary supplements made in the United States caused by manufacturing and labeling errors.
  
  
  METHODS
  Case histories were obtained, and serial laboratory data (calcium and vitamin D metabolites) were measured. Each dietary supplement was analyzed by UV spectrophotometry followed by HPLC.
  
  
  RESULTS
  In both cases, repetitive inquiries were required to elicit the use of dietary supplements. Because of significant manufacturer errors and a labeling error, patients had been consuming more than 1000 times the recommended daily dose of vitamin D(3). Hypercalcemia is directly proportional to serum 25-hydroxyvitamin D [25(OH)D] but not 1,25-dihydroxyvitamin D levels. It took approximately 1 yr to normalize 25(OH)D levels. However, once 25(OH)D levels decreased below 400 ng/ml, both patients became normocalcemic and asymptomatic without long-term sequelae.
  
  
  CONCLUSIONS
  Although rare, vitamin D intoxication should be considered in the differential diagnosis of hypercalcemia. Patients should be asked whether they are using dietary supplements, and serial questioning may be required because patients may not consider these supplements to be potential health risks. Errors in the manufacturing and labeling of dietary supplements made in the United States may place individuals at increased risks for side effects.
authors.affiliation: Division of Endocrinology, Beth Israel Medical Center, 317 East 17th Street, New York, New York 10003, USA.
authors.forename: Takako
authors.initials: T
authors.lastname: Araki
authors.forename: Michael F
authors.initials: MF
authors.lastname: Holick
authors.forename: Bianca D
authors.initials: BD
authors.lastname: Alfonso
authors.forename: Esti
authors.initials: E
authors.lastname: Charlap
authors.forename: Carla M
authors.initials: CM
authors.lastname: Romero
authors.forename: Dahlia
authors.initials: D
authors.lastname: Rizk
authors.forename: Lisa G
authors.initials: LG
authors.lastname: Newman
mesh_terms: D000328:Adult; D019587:Dietary Supplements / Q000009:adverse effects*; D004348:Drug Labeling; D006801:Humans; D006934:Hypercalcemia / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D014807:Vitamin D / Q000506:poisoning*
chemical_list: D014807:Vitamin D