mrsD -

If I may, the last two links in your post - actually they appear to be the same, from www.Drugs.com - strike me as somewhat alarmist. Specifically, I set my search so that it produced a list of "Medications known to interact with quinidine," and got 135 hits for each of the two links. But then randomly sampling maybe 20 drugs, the same operative language is repeated over and over:

Theoretically, co administration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s). Clinically significant prolongation of QT interval and hypokalemia occur infrequently when beta-2 adrenergic agonists are inhaled at normally recommended dosages. However, these effects may be more common when the drugs are administered systemically or when recommended dosages are exceeded. [Emphasis added.]

So to begin with, the list of "Medications known to interact with quinidine" is, with respect to a large number of the drugs listed, is seemingly modified by "theoretically." (Interesting use of "known.") That, and while "the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable," "the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved," whatever that means.

Then it is suggested that those at greatest risk have preexisting conditions that would - with the catch all exception of generic "cardiac disease" - would be picked up by the EKG that we both agree should be mandatory before Nuedexta is used. And as to generic "cardiac disease," I raised that issue a couple of months ago with my cardiologist, where I had a non-transmural MI in 2004 due to a 100% (and chronic by the time it was spotted) occlusion of the mid-LAD, resulting in a 15 - 16% loss of muscle tissue in my left ventricle: but fortunately not enough to affect my ejection fractions. But as to the issue of quinidine, my doctor - who by my dumb luck is currently the President Elect of the American College of Cardiology - told me that, with a normal Q - T interval, he didn't see that taking the drug would be an issue.

Finally - and perhaps most importantly - there is the issue of just what constitutes a recommended dosage, when the website notes concern "when recommended dosages are exceeded." So what are typical doses of quinidine sulfate for cardiac related issues? Significantly higher than Neudextra's 20 mg./day:

Hypertension: Recommended Dose: 100-200 mg daily given as a single dose in the morning or in divided doses (morning and evening). If needed, other antihypertensive agents may be added.

Long-term antihypertensive treatment with metoprolol in daily doses of 100-200 mg has been shown to reduce total mortality, including sudden cardiovascular death, stroke and coronary events in hypertensive patients.

Angina Pectoris: Recommended Dose: 100-200 mg daily given in divided doses (morning and evening). If needed, other antianginal agents may be added.

Cardiac Arrhythmias: Recommended Dose: 100-200 mg daily given in divided doses (morning and evening). If needed, other antiarrhythmic agents may be added.

Maintenance Treatment After Myocardial Infarction: Long-term oral treatment with metoprolol in doses of 200 mg daily given in divided doses (morning and evening) has been shown to reduce the risk of death (including sudden death) and to reduce the risk of reinfarction (also in patients with diabetes mellitus).

Functional Heart Disorders with Palpitations: Recommended Dose: 100 mg once daily given as a single dose in the morning. If needed, the dose can be increased to 200 mg. [Emphasis added.]

http://www.mimsonline.com/Philippine...nidine,sulfate

Indeed, the only drug interaction I happened to come across in the Drugs.com site with hard data concerned the co-administration of quinidine and methadone, where the mean amount of quinidine administered was 400 mg./day, or 20 times that of Nuedexta. http://www.drugs.com/drug-interactio...-0-1981-0.html

Accordingly, assuming there is a fresh EKG in hand, it is difficult for me to understand the risks posed by Nuedexta. That said, I remain open as always to education.

Mike