RYTHMOL SR vs TAMBOCOR

Independent side-by-side comparison.

Rated against independent regulatory sources·Last updated August 22, 2026·How we rate

Possible drug interaction. RYTHMOL SR and TAMBOCOR are different prescription medicines. Combining or switching between them can cause interactions — talk to a pharmacist or prescriber before making changes. This page is not medical advice.

Attribute	RYTHMOL SR	TAMBOCOR
Rating	70/100	70/100
Pharmacy pays	~$10.51 /30	~$5.39 /30
Type	RX	RX
Active ingredient	PROPAFENONE HYDROCHLORIDE	FLECAINIDE ACETATE
Manufacturer	Glaxosmithkline	Alvogen
Dosage forms	Capsule, extended release	Tablet
Drug class	Antiarrhythmic	Antiarrhythmic
Boxed warning	None	None
Half-life	about 2 to 10 hours (immediate-release) in the ~90% of adults who are extensive CYP2D6 metabolizers	—
Treats	Atrial Fibrillation, Supraventricular Tachycardia	Atrial Fibrillation, Supraventricular Tachycardia, Ventricular Tachycardia

rythmol sr tambocor

Rating

70/100

Pharmacy pays

~$10.51 /30

~$5.39 /30

Type

Active ingredient

PROPAFENONE HYDROCHLORIDE

FLECAINIDE ACETATE

Manufacturer

Glaxosmithkline

Alvogen

Dosage forms

Capsule, extended release

Tablet

Drug class

Antiarrhythmic

Boxed warning

None

Half-life

about 2 to 10 hours (immediate-release) in the ~90% of adults who are extensive CYP2D6 metabolizers

—

Treats

Atrial Fibrillation, Supraventricular Tachycardia

Atrial Fibrillation, Supraventricular Tachycardia, Ventricular Tachycardia

Frequently asked questions

Which is better-rated, Rythmol SR or Tambocor?

Rythmol SR and Tambocor are tied at 3.5 out of 5 by our independent rating.

Which is cheaper, Rythmol SR or Tambocor?

Tambocor costs pharmacies less to acquire — about $5.39 vs $10.51 for a 30-count supply, per the CMS NADAC survey. That gap is in the pharmacy's cost of goods, not necessarily in what you pay: your price is set afterwards by your insurer and the pharmacy.

What is the difference between Rythmol SR and Tambocor?

Rythmol SR contains Propafenone Hydrochloride, while Tambocor contains Flecainide Acetate — they have different active ingredients.

Ratings are based on FDA regulatory (recall-safety) data. This comparison is for general reference only — not medical advice. Always consult a licensed professional before choosing or switching a medication.