Switching from Metoprolol Tartrate to Metoprolol Succinate

I've read instructions saying that you can stop taking the metoprolol tartrate and start taking the metoprolol succinate the next day. No need to wean off anything as you're still taking the same medication- just switching from the shorter acting version to an extended release type.

Many years ago I switched the other way around, from metoprolol succinate to metoprolol tartrate. Same instructions.

My cardiologist switched me from metoprolol 50 mg to met succinate 50 mg, stopped tartrate and started succinate same day. No new side effects, just a continuation of loss of energy that I have always had from metoprolol.

@osgilian Both beta blockers, one is slow release. So, if you start the new med the next day, no real change, just slower delivery.

So, to 'how long before it clears the body', the half-life of metoprolol is about five hours, give or take the individual's metabolism of it. This means that in 15 hours your blood still contains about 1/4 of the last dose.

@gloaming I took met. tartrate at 1:30 a.m. I typically take met. succinate at 6:30 a.m. Should I skip the met. succinate or take it later in the day or wait till tomorrow a.m. to take it? And if I wait till tomorrow, should I take another met. tartrate at 1:30 p.m., as that's a 2x/day med?? I'm very confused.

@lj1952 I can't advise you in good conscience because I am unqualified and don't know the rest of your medical history. Why are you taking two kinds of metoprolol? Were you given instructions about how to use both prescriptions?

The tartrate formula is normally twice each day at a prescribed dose. It's the formula that is most easily passed through your system and that's why it needs two doses. The succinate formulation is longer lasting and is often/most usually only dosed once each day. However, it's also meant to be THE dose for the entire 24 hours.
https://www.drugs.com/metoprolol.html

@gloaming Thank you so much for replying so quickly. I was given the tartrate for instances when my HR exceeded 100 for over 10 minutes. This happened around 1:30 this morning--ramping up to 120 (I know that's not high for many people, but it felt like my heart was rocketing out of my chest, to me; the HR of 108 woke me up from a sound sleep). So the tartrate was Rx'd for only such incidents as that, of which there've been very, very few. (For some reason, nitroglycerin was Rx'd and then removed from my meds.)
I was Rx'd succinate to take daily.
I was writing to find out if it would be dangerous to overlap these meds' periods of effectiveness. Since then, I've had a call from my doctor's nurse at about 9:15. She assured me, after checking with my cardiologist, that it was OK, and that I could go ahead and take the succinate. She was going to check back with him to see if he had an alternative to tartrate in mind for instances of HR excursion above 100, sustained for 10 or more minutes.
I understand that succinate is the entire daily dose--it's in extended-release form--for 24 hours. However, there are rare occasions when my HR exceeds a threshold and time period *during a period of inactivity*; my doctor was worried about those periods.
(UPDATE: I'm waiting to see if he has something in mind to replace tartrate and hope to hear from the nurse this morning sometime.)
Thank you again for such a prompt reply!! 🙂

@lj1952 All good, it seems, except for the nasty symptoms. Been there myself, and my rate went as high as 180.

So, yes, the protocol you describe is often used for anti-arrhythmic drugs when the need arises, but the drug is not meant to be taken routinely as metoprolol and statins are, as examples. This acute approach is known as 'PIP' or 'pill-in-pocket.' Flecainide, an anti-arrhythmic drug, is often prescribed that way for paroxysmal AF when AF is relatively infrequent. Your prescriber has offered you the same convenience. After all, who wants to lie awake until dawn?

It seems a good many people experience AF either when they lay back in bed for the night or later on and are aroused by it. Believe it or not, I was the exact opposite. My heart would often act up after supper, my largest meal of the day (hint for those looking for 'triggers' of AF). My heart would be somewhat lumpy all evening, and it would also be a bit cranky as I lay back on my pillow. A few minutes later, having had that quick first nod-off, and then come awake again, often to turn on my side and drift off again, with 100% reliability my heart would be in NSR and remain there all night. I never once, not a single time had that fail or arouse me later. Amazing. So, we all have unique paths to trudge along with this nasty disorder.

To conclude, your PIP protocol for tartrate seems quite reasonable....to me. It should begin to work within about 15-20 minutes or so, and it will hopefully calm your heart and allow you to return to sleep.