Benzbromarone is a uricosuric

Uricosuric

Uricosuric medications are substances that increase the excretion of uric acid in the urine, thus reducing the concentration of uric acid in blood plasma. In general, this effect is achieved by action on the proximal tubule...

 agent used in the treatment of gout

Gout

Gout is a medical condition usually characterized by recurrent attacks of acute inflammatory arthritis—a red, tender, hot, swollen joint. The metatarsal-phalangeal joint at the base of the big toe is the most commonly affected . However, it may also present as tophi, kidney stones, or urate...

, especially when allopurinol

Allopurinol

Allopurinol is a drug used primarily to treat hyperuricemia and its complications, including chronic gout.- Mechanism of action :...

, a first-line treatment, fails or produces intolerable adverse effects

Adverse drug reaction

An adverse drug reaction is an expression that describes harm associated with the use of given medications at a normal dosage. ADRs may occur following a single dose or prolonged administration of a drug or result from the combination of two or more drugs...

. It is structurally related to the antiarrhythmic

Antiarrhythmic agent

Antiarrhythmic agents are a group of pharmaceuticals that are used to suppress abnormal rhythms of the heart , such as atrial fibrillation, atrial flutter, ventricular tachycardia, and ventricular fibrillation....

 amiodarone

Amiodarone

Amiodarone is an antiarrhythmic agent used for various types of tachyarrhythmias , both ventricular and supraventricular arrhythmias. Discovered in 1961, it was not approved for use in the United States until 1985...

.

Benzbromarone is highly effective and well-tolerated, and clinical trial

Clinical trial

Clinical trials are a set of procedures in medical research and drug development that are conducted to allow safety and efficacy data to be collected for health interventions...

s as early as 1981 and as recently as April 2008 have suggested it is superior to both allopurinol and probenecid

Probenecid

Probenecid is a uricosuric drug that increases uric acid excretion in the urine. It is primarily used in treating gout and hyperuricemia.Probenecid was developed as an alternative to caronamide...

, another uricosuric drug.

Effect on cytochrome P450

Benzbromarone is a very potent inhibitor

Enzyme inhibitor

An enzyme inhibitor is a molecule that binds to enzymes and decreases their activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used as herbicides and pesticides...

 of CYP2C9

CYP2C9

Cytochrome P450 2C9 is a protein that in humans is encoded by the CYP2C9 gene.- Function :CYP2C9 is an important cytochrome P450 enzyme with a major role in the oxidation of both xenobiotic and endogenous compounds. CYP2C9 makes up about 18% of the cytochrome P450 protein in liver microsomes...

. Several analogues

Analog (chemistry)

In chemistry, a structural analog , also known as chemical analog or simply analog, is a compound having a structure similar to that of another one, but differing from it in respect of a certain component. It can differ in one or more atoms, functional groups, or substructures, which are replaced...

 of the drug have been developed as CYP2C9 and CYP2C19

CYP2C19

Cytochrome P450 2C19 , a member of the cytochrome P450 mixed-function oxidase system, is involved in the metabolism of xenobiotics in the body. It is involved in the metabolism of several...

inhibitors for use in research.

Safety

Benzbromarone was introduced in the 1970s and was viewed as having few associated serious adverse reactions. It was registered in about 20 countries throughout Europe, Asia and South America.

In 2003, the drug was withdrawn by Sanofi-Synthélabo, after reports of serious hepatotoxicity, although it is still marketed in several countries by other drug companies.