quinidine


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Related to quinidine: quinine, Quinidine sulfate

quinidine

(kwĭn`ĭdēn'), heart muscle relaxant used to maintain regular heart rhythm patterns. It is an alkaloidalkaloid,
any of a class of organic compounds composed of carbon, hydrogen, nitrogen, and usually oxygen that are often derived from plants. Although the name means alkalilike, some alkaloids do not exhibit alkaline properties.
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 chemically similar to quininequinine
, white crystalline alkaloid with a bitter taste. Before the development of more effective synthetic drugs such as quinacrine, chloroquine, and primaquine, quinine was the specific agent in the treatment of malaria.
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 and, like quinine, occurs naturally in some species of cinchona trees. Quinidine slows the rate of blood flow in heart chambers and lowers the excitability of the muscle. Quinidine is a general relaxant of smooth muscle and acts as a dilator of larger blood vessels. It has also been used to reduce fever and to treat malaria. Synchronized electric shock has largely replaced quinidine as a method of establishing more normal heart rhythms.

quinidine

[′kwin·ə‚dēn]
(organic chemistry)
C20H24N2O2 A crystalline alkaloid that melts at 174-175°C (345-347°F) and that may be derived from the bark of cinchona; used as the salt in medicine. Also known as β-quinine.
References in periodicals archive ?
21) Quinidine can be associated with significant QTc prolongation when dosed at antiarrhythmic levels, although mean plasma concentrations found with the 10 mg of quinidine in the approved DM/Q formulation are 1% to 3% of those associated with typical dosages used in antiarrhythmic therapy.
With quinidine, we can use smaller dosages of dextromethorphan" than might be required if the drug were used by itself and thereby avoid the lethargy that could occur in patients who might require larger dosages of dextromethorphan without quinidine, he said in an interview.
After 10 weeks, the 93 patients on dextromethorphan plus quinidine had their average neuropsychiatric inventory domain score for agitation and aggression cut roughly in half, compared with baseline, compared with about a 25% drop in average score among 66 control patients, a statistically significant difference for the study's primary endpoint, Dr.
Parenteral artesunate, an artemisinin that is a first-line treatment for severe malaria in many countries, is associated with increased survival and has a better safety profile than the parenteral alternatives, quinine and quinidine.
As noted earlier, cardiac toxicity has been a major concern with the use of IV quinine or quinidine, with quinidine considered to be more 4,6 toxic than quinine .
Co-administration of cisapride, dofetilide, ergot alkaloids such as dihydroergotamine, ergotamine, ergometrine (ergonovine), and methylergometrine (methylergonovine); felodipine, levacetylmethadol (levomethadyl), lovastatin, methadone, oral midazolam, nisoldipine, pimozide, quinidine, simvastatin, and triazolam with ONMEL[TM] is contraindicated.
Dextromethorphan, dextrorphan, quinidine, chlorpheniramine, [beta]-nicotinamide adenine dinucleotide phosphate (NADP), D-glucose 6-phosphate, glucose 6-phosphate dehydrogenase, heparin sodium, urethane, and phenacetin were from Sigma Chemical Co.
Treatment may include "shocking" the heart (a process called cardioversion) and/or the use of anti-arrhythmics, such as quinidine, and anticoagulants, such as warfarin (Coumadin).
That makes it pretty hard to keep coming up with something that hasn't already been taken in a field that includes such familiar products as Xanax, Zantac, Zocor, Zoloft, Prozac, Maxzide, Zithromax, Thorazine, Quinidine and Tylox.
The subsequent chapters provide details on specific drugs: aminoglycosides, vancomycin, digoxin, lignocaine, procainamide, quinidine, phenytoin, carbamazepine, valproate, phenobarbitone, ethosuximide, cyclosporin, tacrolimus, lithium and theophylline.
Although quinine is used throughout most of the world for severe cases of malaria, quinidine is the only parenteral medication approved in the United States and
Rhodamine B, ([+ or -])-verapamil hydrochloride, and quinidine were purchased from Sigma Chemical Company (St.