D. Calhoun et al., FENOLDOPAM - A NOVEL, PERIPHERALLY ACTING DOPAMINE-1 AGONIST FOR PARENTERAL TREATMENT OF HYPERTENSION, Medicamentos de actualidad, 33(10), 1997, pp. 729-738
Fenoldopam mesylate is a novel, peripherally acting dopamine-1 recepto
r agonist that induces potent arteriolar vasodilatation of renal, mese
nteric, coronary and skeletal muscle vasculature. Clinical studies ind
icate that fenoldopam reduces blood pressure in a linear, dose-depende
nt fashion in healthy subjects and in patients with mild, moderate or
severe hypertension. The reduction in blood pressure is attributable p
rimarily to a reduction in peripheral vascular resistance. In hyperten
sive subjects with and without renal insufficiency, fenoldopam tends t
o increase renal blood flow and has significant natriuretic and diuret
ic properties, as indicated by substantial increases in sodium and fre
e water excretion and urine flow. Fenoldopam has a rapid onset of acti
on (5 min) and short duration of action (30 min) when administered int
ravenously. Little if any tachyphylaxis is observed in blood pressure
reduction with up to 24 h of infusion, and no rebound hypertension occ
urs upon abrupt cessation of therapy. Fenoldopam is metabolized quickl
y, with no accumulation of toxic degradation products. Fenoldopam is w
ell tolerated. The most common adverse events associated with the comp
ound, flushing and headache, are attributable to its vasodilator actio
n. In heart failure patients, fenoldopam reduces systemic vascular res
istance while increasing cardiac output. Unlike nitroprusside, fenoldo
pam is not a venodilator, and does not consistently reduce pulmonary c
apillary wedge pressure. Interestingly, the natriuretic/diuretic prope
rties of fenoldopam observed in hypertensive patients have not been co
nsistently observed in heart failure patients. Fenoldopam has been sho
wn to safely reduce postoperative hypertension in patients undergoing
both cardiac and noncardiac surgery. In a study of patients recovering
from coronary artery bypass grafting, decreases in urine flow associa
ted with nitroprusside were not seen with use of fenoldopam. In these
same postoperative patients, nitroprusside use was associated with red
uctions in pulmonary capillary wedge pressure while fenoldopam was not
. Fenoldopam is a promising alternative to nitroprusside for intraveno
us reduction of blood pressure. Clinical comparisons indicate antihype
rtensive efficacy and safety similar to nitroprusside. Fenoldopam has
a rapid but not abrupt onset of action such that use of an intraarteri
al line to monitor blood pressure can be avoided. Compared with nitrop
russide, fenoldopam tends to increase renal blood flow and to increase
sodium and free water excretion, which may De clinically advantageous
in certain subsets of patients. Fenoldopam will likely be more conven
ient to use than nitroprusside as it is not photosensitive and none of
its metabolites arts toxic.