Leary WP, Reyes AJ
Magnesiuretic potency of twenty-seven oral formulations of
diuretics: report on a study series in progress
American Soc Hypertension (ASH)
Am J Hypertens
(May) 13:113A 2000

The responses of mean 24-h magnesiuresis (MM) and natriuresis (MN)
to single doses of twenty-seven oral formulations of diuretics have
thus far been evaluated in sixteen studies, thirteen of which were
individually randomized, crossover, double-blind and placebo
controlled (pre-treatment MM and MN served as controls in the three
open trials).
In each study, 7-19 healthy adults staying in a metabolic unit
received one (open studies) or more treatments (on conveniently
separated single-treatment days). The study series (n = 198
volunteers) control MM was 4.6 mmol; MN had a study series control
value of 161 mmol. Results refer to changes with respect to control
MM and MN in each study.
Thiazide-type diuretics: cicletanine (CICL) 50 and 150 mg did not
modify (p > 0.05) MM, but they raised (p < 0.05) MN by 26 and
49%; CICL 100 mg, clopamide 5 mg, clorexolone 10 mg, chlorthalidone
100 mg, hydrochlorothiazide (HCTZ) 25 mg (which was tested in two
studies), HCTZ 50 mg (which was tested in two studies), and
xipamide 5, 10, 20 and 40 mg increased MM between 17 and 87% and MN
between 47 and 165%.
Loop diuretics: muzolimine (MUZ; this substance is no longer
available) 20, 30 and 40 mg and torasemide (TOR) 2.5, 5 and 10 mg
did not change MM (MUZ 20 mg and TOR 2.5 mg did not change MN,
whereas MUZ 30 and 40 mg and TOR 5 and 10 mg raised it between 17
and 34%); furosemide (FUR) 80 mg and TOR 20 mg raised MM by 20 and
24% and MN by 86 and 78%.
Potassium-retaining diuretics: amiloride (AMI) 5 and 10 mg did not
change MM, but they raised MN by 38 and 66%; spironolactone (SPIR)
100 mg did not change MM nor MN.
Combinations: FUR 40 mg & AMI 5 mg, FUR 80 mg & AMI 10 mg, HCTZ 50
mg & AMI 5 mg, and HCTZ 25 mg & SPIR 100 mg did not modify MM, but
they raised MN between 64 and 88%.
Roughly, MM paralleled MN after loop and thiazide-type diuretics.
MUZ 20 mg and TOR 2.5 mg, both of which are loop diuretics and are
provenly effective once-daily antihypertensive
monopharmacotherapies, did not raise MM and were the only
formulations tested that qualified as very-low-dose formulations,
since they did not increase MN.
© Copyright 2000 American Journal of Hypertension, Ltd.
Reproduced with permission from ASH and Elsevier.