Pharmacokinetics of calcium absorption from two commercial calcium supplements

H. J. Heller, A. Stewart, S. Haynes, C. Y C Pak

Research output: Contribution to journalArticlepeer-review

55 Scopus citations


This study was conducted to compare pharmacokinetic indices of calcium absorption after a single oral (500 mg calcium) load of Citracal (calcium citrate) and Os-Cal (calcium carbonate). In 18 postmenopausal normal women, venous blood samples were obtained for the measurement of calcium before and hourly for 6 hours after an oral ingestion of Citracal, Os-Cal, or placebo with a breakfast meal. The change in area under the curve (ΔAUC) in serum calcium from preload was 2.5-fold greater for Citracal than Os-Cal, and the peak-basal variation in serum calcium was 76% higher for Citracal than Os-Cal. The increment in serum calcium from preload after Citracal administration was significantly higher than that obtained after placebo load during most time periods and significantly higher than that of Os-Cal at 1, 4, and 5 hours after load. In contrast, (ΔAUC) and peak basal variation of Os-Cal did not differ significantly from placebo, and increment in serum calcium was significantly increased from placebo only at 6 hours. In conclusion, Citracal is much more bioavailable than Os-Cal. (C) 1999 the American College of Clinical Pharmacology.

Original languageEnglish (US)
Pages (from-to)1151-1154
Number of pages4
JournalJournal of clinical pharmacology
Issue number11
StatePublished - 1999

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)


Dive into the research topics of 'Pharmacokinetics of calcium absorption from two commercial calcium supplements'. Together they form a unique fingerprint.

Cite this