Extreme fatigue from Metoprolol?

73 yo female on 75 mg metoprolol for left bundle branch block. I've never been as active as you certainly have, but I do have fatigue made worse by the metoprolol, and at the gym it is difficult to get my heart rate up on the treadmill or the elliptical. It can get frustrating.

Metoprolol is a beta blocker (beta adrenergic) that is used for both incipient hypertension and as a rate control medication. It affects rate AND force. It not only helps to keep a lid on a tachyarrhythmia, which both AVT and AF are (AF not always is above 100 BPM, so it is only classified as a tachyarrhythmia if it presents above 100 BPM)), but it can make the heart less 'cooperative' during high demand activity such as stair climbing, trail running in hills, etc. I complained to my cardiologist that I simply could not, for the life of me, run with the same energy or speed as prior to my diagnosis and his prescriptions (apixaban and metoprolol, plus he feared ischemia and wanted me on a statin right away). He replied that I cannot blame metoprolol for my reduced capacity. I know better, but in Canada the medical system is state-run and they get to call the shots.

@gloaming There is a lot of information on beta blockers limiting maximum heart rate. Hopefully there is a solution out there. Maybe an ablation procedure.

I am an 82 year old female. I have been active all my life for a female born in 1940s when, in the succeeding years, it was considered unladylike to sweat. I cut the dose in half for awhile and successfully finished an uphill hike in Zion National Park that was deemed "moderate". I belong to a very wonderful hiking group (all younger- under 70) and they offer support and encouragement when I hike with them.

Both my primary care and pulmonologist have given me permission to discontinue Metoprolol. I can't say I am a bundle of energy, but I do feel better without it. I am on BIPAP with oxygen at night. I do what I call a minihike with the man in my life and his dog most mornings for two to three miles and do pilates and aerial yoga an hour each during the week. I'm a firm believer in exercise being key to wellness. But age does have its limitations. Luckily I have all my parts and no pain so that make the exercise easier than for those who are not so lucky.

Wishing you good luck on your journey of finding what works for you.

@afm Thank-you. It turns out that I have had two RF ablations, of which only the second has worked, now within three days of three full years free of AF. 😀 In case others reading are learning about AF, catheter ablation is considered to be the gold standard of care now for atrial fibrillation (AF). There are other ways to manage the disorder, at least one with generally very good and permanent results (Cox-Maze procedure). Most, including unfortunately ablations, tend not to be permanent. The majority of ablations are likely to fail in time, some in months, some in quite a few years. This is due to the progressive nature of the disorder which encourages the heart to keep producing more and more rogue firing cells in the substrate of the myocardium. Eventually, if a heart beats long enough, it might find itself in permanent AF because no treatment will suffice. None of this is a sure thing because each case is different and there is a lot of variance between bodies. It's just a tendency, and that's why we say that there is no cure for AF, despite what some cardiologists suggest. It can be controlled, put off, delayed, but it progresses all along and it will do so in the majority of patients. What ablation does is to forestall the changes that come with persistent and permanent AF where the heart remodels itself in time by thickening its vessel walls, developing fibrosis, and often causing the mitral valve to prolapse. This usually takes years, but it does happen, and ablations delay that process for as long as they keep the heart in normal sinus rhythm. Three years so far...for me.

One last statement, and it's important: AF does not kill. You are virtually certain to die from cancer at a ripe old age, or a heart attack due to blockages, maybe diabetes, maybe heartache from the loss of a mate, but you won't die from AF.

Yep. Similar experience in 2022 Utah hiking trip. AF history including 2017 Ablation. No meds or OACs but on a stopover in Colorado on the way to Utah experienced a too long to ignore AF episode, to ER where I was stabilized and AF ceased. Dr prescribed that I take Metropolol. During the subsequent hiking I found I was exhausted most of the time especially during uphill sections. After a couple of days of this I decided to stop the metropolol and my energy returned. I will do most anything to stay off beta blockers or anti arrhythmia drugs.

@dalebout123 Thanks. That's encouraging. Why were you prescribed Metoprolol? In my case a 24 hour Holter monitor showed SVT. I was prescribed something (can't remember) and felt much better. A second 24 hour Holter monitor then showed no SVT but Afib 90% of the time. Was prescribed 25 mg of Metoprolol per day and that's when the problem with climbing started. After a one month Holter showed no Afib but continued problems with climbing a second one month Holter was done. A second cardiologist then thought that although the Afib was gone that the SVT might still be there. So the Metoprolol dosage was increased to 50 mg per day (25 mg in the morning and 25 mg at night). Also take Pradaxa - blood thinner. After a time delay due to travel and weather I was finally able to get out for some climbing hikes and again had extreme fatigue and dizziness when climbing on a 8 mile hike which I used as a recovery hike 2 years ago. I have a message in to my cardiologist on all this but haven't heard back. He knows the history and my goals and is working with me.

I am ready to dump the Metoprolol. I have identified a very nice 25 mile dead flat hike on the Lost Coast Trail in northern California.

@chickenfarmer Thanks. I have no perception of Afib or SVT even when diagnosed with Afib 90% of the time and one bout of heart rate at 185 bpm for 16 minutes on the Holter monitor data. My only symptom was feeling very tired in the mornings and feeling very tired on one day of a multi day back packing trip. I am certainly open to trying an ablation procedure and going off the Metoprolol. For the last 30 years I have a history of running and endurance cycling as well as bicycle racing. It is very discouraging to basically "blow up" walking uphill. But many others have it far worse.

You might be interested in the book "The HAywire Heart" which lays out the case for increased AF cases among uber endurance athletes. In "You Cant Scare me" the author and uber athlete details his AF battle. I read one Dr article that said Tour De France riders are 5x as likely to experience AF than general population. Another good book is "the AFIB Cure" by a couple of cardiologists who are also very athletic. My advice for you based upon your brief description is to get a better handle on your AF - visit a Electrophysiologist and explain your symptoms. Also get a smartwatch to monitor your heart rhythm so you have a better understanding of how much heart Arrhythmias you have. I find Af to be another factor in my life that I must accomodate but beyond that life as normal and I'm still on the bike at age 77.
Some other things to consider if you find you have AF which requires treatment: Ablation is now recognized as the best treatment compared with drugs which have side effects and effectiveness deteriorates with time. Ablations are safer due to new technology Pulsed Field so make sure you read latest info, not stuff that is even 5 yrs old. The sooner you get treatment the better your outcome AF left untreated gets worse with time. Ablatrion is a good treatment but not a silver bullet the average period before AF reoccurence after ablation is 5 yrs which i can attest to. We have a bike group of 4 old geezers and 3 of us have been diuagnosed and had ablations.

@afm
I am currently on a daily dose of 25 mg metoprolol and I don't really notice it. When I go cross country skiing my HR will sometimes go above 150 BPM and then return to 50-60 BPM at rest. Prior to my ablation in January 2025, I was taking 75 mg of metoprolol, which gave me a case of the zombies. After the ablation, my cardiologist lowered my dose to 50mg, then to 25mg, and said I can discontinue it altogether is my HR goes to 50 or below during rest. When sleeping, my Apple Watch often clocks my HR in the mid 40s.