Efficacy of chewed vs. crushed lanthanum on phosphorus binding in healthy volunteers.
OBJECTIVE
For effective dietary phosphorous (P) binding, patients are recommended to chew lanthanum tablets completely before swallowing, with or immediately after meals. However, some patients are unable to chew the tablets. It is not known if crushing the tablets prior to taking them with food is as efficacious as chewing them. This study was conducted to compare the efficacy of chewed vs. crushed lanthanum on P binding.


METHODS
12 healthy subjects were randomized and crossed-over to receive: (A) a standardized meal containing 1 g (32 mmol) of elemental P; (B) a single 1 g oral dose of lanthanum, chewed and taken with the standardized meal; (C) a single 1 g oral dose of lanthanum, crushed into a fine powder using a pestle and mortar, mixed with applesauce, and taken with the standardized meal. Blood and urine samples were collected from baseline to 8 hours after meal completion. The changes in serum P, urinary P excretion and fractional excretion of P (FePi) were compared among treatment arms using ANOVA.


RESULTS
Co-administration of lanthanum with meal resulted in a smaller increase in serum P, compared with meal alone (p < 0.05). The smaller increase in serum P was similar for both chewed and crushed lanthanum. The amount of P excreted and FePi were also lower when chewed or crushed lanthanum was administered with meal, compared with meal alone (p = n.s. and p < 0.05, respectively).


CONCLUSIONS
Both chewed and crushed lanthanum are effective in lowering P absorption after a dietary P load.
How
P P
PP
Department of Pharmacy, Faculty of Science, National University of Singapore, Block S4, Science Drive 4, 117543 Singapore. priscillahow@nus.edu.sg
Mason
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DL
Arruda
J A
JA
Lau
A H
AH
D000284:Administration, Oral; D000328:Adult; D018592:Cross-Over Studies; D005260:Female; D005502:Food; D006801:Humans; D007811:Lanthanum / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D008297:Male; D008409:Mastication; D016226:Phosphorus, Dietary / Q000378:metabolism*; D011208:Powders; D012016:Reference Values; D013607:Tablets; D055815:Young Adult
D016226:Phosphorus, Dietary; D011208:Powders; D013607:Tablets; C119467:lanthanum carbonate; D007811:Lanthanum