Recent from talks
Quinidine
Knowledge base stats:
Talk channels stats:
Members stats:
Quinidine
Quinidine is a class IA antiarrhythmic agent used to treat heart rhythm disturbances. It is a diastereomer of antimalarial agent quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. As of 2019, its IV formulation is no longer being manufactured for use in the United States.
Quinidine is occasionally used as a class I antiarrhythmic agent to prevent ventricular arrhythmias, particularly in Brugada Syndrome, although its safety in this indication is uncertain.
It reduces the recurrence of atrial fibrillation after patients undergo cardioversion, but it has proarrhythmic effects and trials suggest that it may lead to an overall increased mortality in these patients.
Quinidine is also used to treat short QT syndrome.
Eli Lilly has discontinued manufacture of parenteral quinidine gluconate in the US, and its future availability in many countries is uncertain.
There is one study supporting the use of a novel combination of dextromethorphan and low dose quinidine in alleviating symptoms of easy laughing and crying (pseudobulbar affect); these are a type of rather severe uncontrollable behaviors which can be present in various neurological pathologies such as amyotrophic lateral sclerosis and multiple sclerosis. The dose of quinidine (10 mg two times daily) is about 1/40th of a relatively low antiarrhythmic dose (400 mg, twice or 3 times daily, as an example; antiarrhythmic doses can sometimes exceed 1500 mg/day). The authors did not observe significant safety risks using the low quinidine dose, but urged caution and also pointed out that quinidine interacts with a large number of other medications in dangerous or unpredictable ways. A meta analysis was published referencing only that one study.
Although intravenous quinidine is sometimes used to treat Plasmodium falciparum malaria, the future availability of this agent is uncertain.
Quinidine is an inhibitor of the cytochrome P450 enzyme 2D6, and can lead to increased blood levels of lidocaine, beta blockers, opioids, and some antidepressants. Quinidine also inhibits the transport protein P-glycoprotein and so can cause some peripherally acting drugs such as loperamide to have central nervous system side effects, such as respiratory depression, if the two drugs are coadministered.
Hub AI
Quinidine AI simulator
(@Quinidine_simulator)
Quinidine
Quinidine is a class IA antiarrhythmic agent used to treat heart rhythm disturbances. It is a diastereomer of antimalarial agent quinine, originally derived from the bark of the cinchona tree. The drug causes increased action potential duration, as well as a prolonged QT interval. As of 2019, its IV formulation is no longer being manufactured for use in the United States.
Quinidine is occasionally used as a class I antiarrhythmic agent to prevent ventricular arrhythmias, particularly in Brugada Syndrome, although its safety in this indication is uncertain.
It reduces the recurrence of atrial fibrillation after patients undergo cardioversion, but it has proarrhythmic effects and trials suggest that it may lead to an overall increased mortality in these patients.
Quinidine is also used to treat short QT syndrome.
Eli Lilly has discontinued manufacture of parenteral quinidine gluconate in the US, and its future availability in many countries is uncertain.
There is one study supporting the use of a novel combination of dextromethorphan and low dose quinidine in alleviating symptoms of easy laughing and crying (pseudobulbar affect); these are a type of rather severe uncontrollable behaviors which can be present in various neurological pathologies such as amyotrophic lateral sclerosis and multiple sclerosis. The dose of quinidine (10 mg two times daily) is about 1/40th of a relatively low antiarrhythmic dose (400 mg, twice or 3 times daily, as an example; antiarrhythmic doses can sometimes exceed 1500 mg/day). The authors did not observe significant safety risks using the low quinidine dose, but urged caution and also pointed out that quinidine interacts with a large number of other medications in dangerous or unpredictable ways. A meta analysis was published referencing only that one study.
Although intravenous quinidine is sometimes used to treat Plasmodium falciparum malaria, the future availability of this agent is uncertain.
Quinidine is an inhibitor of the cytochrome P450 enzyme 2D6, and can lead to increased blood levels of lidocaine, beta blockers, opioids, and some antidepressants. Quinidine also inhibits the transport protein P-glycoprotein and so can cause some peripherally acting drugs such as loperamide to have central nervous system side effects, such as respiratory depression, if the two drugs are coadministered.
Recent media