SUMMARYTwo 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‐NoItabs, to produce peak plasma bismuth concentrations hitherto considered to be in the range associated w