title: The absorption of bismuth from oral doses of tripotassium dicitrato bismuthate.
abstract: Two studies measured plasma concentrations of bismuth during dosing with tripotassium dicitrato bismuthate (De-Noltab). The first study compared 24 h plasma bismuth concentration and urinary bismuth excretion in six patients who had already received 29-131 days (median 47 days) of treatment with De-Noltab 2 b.d., and six healthy subjects who only received De-Noltab 2 b.d. on the day of study. There was a prompt rise in plasma bismuth concentration after each dose of De-Noltabs. The median 24 h integrated plasma bismuth concentration was similar in both groups, but the median 24 h urinary bismuth excretion was 5.4-fold higher in the patients. The second study compared the plasma bismuth concentrations after the first and third doses of De-Noltab 2 b.d. in 16 healthy subjects. The median peak bismuth concentration occurred 30 min (range 15-105 min) post-dosing. The peak plasma bismuth concentration was greater than 50 ng/ml in 14 of the 16 subjects, and greater than 100 ng/ml in nine of the subjects. There was no significant difference in the median integrated 10-h plasma bismuth concentration after the first or third dose of De-Noltabs. The results of these studies confirm that bismuth is absorbed and sequestrated during dosing with De-Noltabs. Bismuth is absorbed rapidly after oral dosing with De-Noltabs, to produce peak plasma bismuth concentrations hitherto considered to be in the range associated with bismuth neurotoxicity.
authors.affiliation: Academic Department of Medicine, Royal Free Hospital School of Medicine, London, UK.
authors.forename: C U
authors.initials: CU
authors.lastname: Nwokolo
authors.forename: C J
authors.initials: CJ
authors.lastname: Gavey
authors.forename: J T
authors.initials: JT
authors.lastname: Smith
authors.forename: R E
authors.initials: RE
authors.lastname: Pounder
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000897:Anti-Ulcer Agents / Q000008:administration & dosage*; D001729:Bismuth / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D006801:Humans; D007408:Intestinal Absorption; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage*; D013054:Spectrophotometry, Atomic
chemical_list: D000897:Anti-Ulcer Agents; D009942:Organometallic Compounds; C002791:bismuth tripotassium dicitrate; D001729:Bismuth