Succinate vs Tartrate

[DKBX]

If one has been taking 2x/day 50mg metoprolol tartrate, is it ok to switch to the succinate form (same dosage 50mg 2x/day). [I already know that the first is short acting and the second extended release.]

The EP says take 100mg (2 tablets of 50) of the succinate at once instead of one in am and one in pm like I’ve been doing with the tartrate …. But I see no difference in keeping up with my normal routine of 50 2x/day just with the succinate instead of the tartrate. Opinions??

[Ppiman]

For advice on taking any tablet, you must only ask your doctor or pharmacist, or refer to the packaging leaflet. The pharmacist's label on the product should also be clear.

Below is my own understanding; however, it must replace official advice:

Metoprolol, originally formulated from the tartrate salt, has a short half life which means that twice daily dosing is needed.

One way to overcome the need for multiple daily doses of a drug is to formulate the active ingredient salt inside an extended-release tablet or capsule. This is often a plastic matrix and it stops all of the active ingredient being released immediately into the stomach, meaning the drug is released as it travels along the small intestine. This allows for once-daily dosing.

For presumably technical or pharmacological reasons, the manufacturers chose to use metoprolol succinate in the extended-release, once-a-day formulation, rather than metoprolol tartrate, which is used in the immediate-release, twice-a-day tablet.

The salts - tartrate or succinate - only matter to the manufacturer, really. To the patient, what matters is whether the tablet is extended release and once-a-day, or immediate release and twice-a-day.

Taking two of the extended release version simply doubles the dose. The tablets will still release over 24 hours, and so need to be taken at the same time.

Steve

[Chrissy7]

Not sure if this helps but…I could not tolerate metoprolol side effects.However when on Diltiazem I definitely saw a difference in the slow release 120 vs short equivalent acting dosage …could only tolerate the short acting meds.

So in my opinion … for what it’s worth .. I say “if it’s not broken… don’t change it.”

Everyone may tell you it’s the same thing - but for me, it was not.

[Snowgirl65]

I take succinate twice a day, and the tartrate only when I'm having an a-fib episode. I honestly don't know if the latter helped stop it.