Plasma atrial natriuretic peptide and the renin-aldosterone system during long-term administration of the diuretic xipamide in man.

We have studied the effect of xipamide on plasma α-atrial natriuretic peptide and the reninaldosterone-kallikrein system in twelve healthy men, using a double-blind cross-over design. After a run-in period on placebo for 1 week the subjects were treated with either placebo (n=6) or xipamide 20 mg once daily (n=6) for 16 weeks and were then switched to the alternative medication for another 16 weeks.