Brands, Medical Use, Clinical Data
Drug Category
- Antihypertensive Agents
- Dopamine Agonists
- Vasodilator Agents
Dosage Forms
Brands / Synonyms
Corlopam; Fenodopam mesylate; Fenoldopam; Fenoldopam mesylate; Fenoldopamum [Latin]
Indications
For the in-hospital, short-term (up to 48 hours) management of severe hypertension when rapid, but quickly reversible, emergency reduction of blood pressure is clinically indicated, including malignant hypertension with deteriorating end-organ function.
Pharmacology
Fenoldopam antagonizes D1-like dopamine receptors, binds to α2-adrenoceptors, increasing renal blood flow.
Mechanism of Action
Fenoldopam is a rapid-acting vasodilator. It is an agonist for D1-like dopamine receptors and binds with moderate affinity to α2-adrenoceptors. It has no significant affinity for D2-like receptors, α1 and β-adrenoceptors, 5HT1 and 5HT2 receptors, or muscarinic receptors. Fenoldopam is a racemic mixture with the R-isomer responsible for the biological activity. The R-isomer has approximately 250-fold higher affinity for D1-like receptors than does the S-isomer. In non-clinical studies, fenoldopam had no agonist effect on presynaptic D2-like dopamine receptors, or α or β -adrenoceptors, nor did it affect angiotensin-converting enzyme activity. Fenoldopam may increase norepinephrine plasma concentration.
Absorption
Not Available
Toxicity
The most likely reaction of overdose would be excessive hypotension which should be treated with drug discontinuation and appropriate supportive measures.
Biotrnasformation / Drug Metabolism
Elimination is largely by conjugation, without participation of cytochrome P-450 enzymes. Methylation, glucuronidation, and sulfation are the main routes of conjugation.
Contraindications
None known.
Drug Interactions
Drug Interactions with Beta-Blockers: Concomitant use of fenoldopam with beta-blockers should be
avoided. If the drugs are used together, caution should be exercised because unexpected hypotension could result from
beta-blocker inhibition of the sympathetic reflex response to fenoldopam.
Drug Interactions, General: Although there have been no formal interaction studies, intravenous fenoldopam has
been administered safely with drugs such as digitalis and sublingual nitroglycerin. There is limited experience with
concomitant antihypertensive agents such as alpha-blockers, calcium channel-blockers, ACE inhibitors, and diuretics
(both thiazide-like and loop).
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