Diltiazem
I've been slowly having fatigue for a few years now, but the last year it has been getting worse.
I was diagnosed with obstructive HCM a year ago and started metoprolol back in November 2024 after an incident of sepsis in the hospital. My fatigue was getting worse since then, so my cardiologist had me back off to half my dose in February after seeing my resting heart rate is between 40-50bpm.
The fatigue hasn't gotten better so he wants me to stop taking metoprolol and see if the fatigue goes away. He said if it does, the backup would be Diltiazem to try next.
Has anyone had this medication and/or gone through this process of trying different medications?
I have some angina, but mostly just fatigue (which could be related to anything). My heart rate has been weirdly all over the place lately. It was fairly low/stable from November through March and then started getting weird the last month. Simple task of getting up to walk to the fridge could go from a 50bpm to 120bpm. No dizziness but feel my heart racing so I check.
My cardiologist is local to me, but I'll be seeing a second opinion in June in a more specialized heart center at Kaiser (Santa Clara) with a cardiologist that was at Stanford's HCM center.
Part of me is wondering if I just wait to make any changes until then but I had not heard of this medication so was wondering of others experience.
Interested in more discussions like this? Go to the Hypertrophic Cardiomyopathy (HCM) Support Group.
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@sjm46 Looks like you’ve done well. I’m over a year since AFIB diagnosis and finally working with an Electrophysiologist in the practice along with my Cardiologist. Good news is since my diagnosis I’ve lost weight, eliminated alcohol completely and walking 3 miles 3 times per week along with light weight training. All that has reduced my AFIB episodes to less than 4% of the time according to my recent 30 day monitor. I rarely know when I’m in AFIB. I do also have LBBB and that’s another issue. Some days I still have little energy but I push through. The EP has mentioned installing a long term Implantable Loop Recorder (ILR) so that when I feel odd, I have the ability to record the event using my cell phone and the event info will be transmitted to the practice. I do have another issue creating in and that is numbness in lower left leg and foot 60% of the time. Even wakes me in the night sometimes. I assume that is. Vein issue, but sure my heart condition is involved. I’ve got a follow up with both EP and Cardilogist along with an echocardiogram early in January. Neither of them seemed to be too concerned, although I feel sometimes my days are numbered.
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2 ReactionsI just came across your WONDERING about Diltiazem. I took Diltiazem for so many years I can not truthfully tell you how many. Rough guess, 10 plus years. I tolerated it extremely well. Never any problems to my knowledge. I fell & broke my rt. hip in April. A new Doctor took me off Diltiazem in the hospital. Now my new primary care Doctor has me on Lisinopril 2 per day. I asked if I could go back on Diltiazem & he told me no because it would not do for my heart what he wants it to do. Also, on Metoprolol half tab. 2x day. To slow my heart down. Best of luck to you from Booarang12
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1 Reaction@boomarang CORRECTION SHOULD BE Boomarang12 on comment for Diltiazem
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1 Reaction@4aces4me I've been taking Diltiazem about a month and a half, I've experience some night sweats, and lots of pain in my body, thank you for information
@boomarang do you take elouis blood thinner? I take metoprolol, tartrate 25 mg twice daily, I also take Lisinopril 20 mg twice daily, plus diltiaxem 120 SR twice a day, I just started the diltiazem about 45 days ago, the other blood pressure meds I have been taking for several years, thank you for the information
@boomarang12. Thank you
@4aces4me Just curious; has the EP discussed an ablation or are you just not interested in going that route? Also, I hear from many people how they don't even know that they are in A-fib. For me, I could tell immediately. Interesting how everyone is different. Are you on Eliquis? My brother has had A-fib for years and his cardiologist never gave him anything except ASA low dose. It does seem that treatment plans are all over the map. I am glad you are doing well. I think life-style changes do make a world of difference for many of us.
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1 ReactionMy Cardiologist and Electrophysiologist have ruled out Ablation since last 30 day Monitor still shows 4% or less. I am on Eliquis 2X daily and tolerate it well. I do believe they will insert a loop monitor soon to be able to see real time events and their effects on my life. Really need to get my circulation issues in my left leg and tingling foot under control. Some nights sleep is a challenge from waking with a throbbing lower leg.
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2 Reactions@4aces4me I hope you get to see a doctor soon 🙋
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1 ReactionThis information is from peer-reviewed studies:
Fatigue is a really common challenge in obstructive HCM, and medications can make it better or worse depending on how your body responds. Metoprolol is often the first-line drug, but for some people it causes bradycardia (low heart rate) and worsening fatigue — especially if your resting HR is already in the 40s–50s. So your cardiologist’s thought process makes sense.
About trying different medications:
• Beta-blockers (like metoprolol): helpful for symptoms, but can slow the heart too much and cause fatigue, low energy, or exercise intolerance.
• Non-dihydropyridine calcium-channel blockers (like diltiazem or verapamil): these are the usual “backup” if beta-blockers aren’t tolerated. They can help with chest discomfort, heart rate control, and symptoms of obstruction without dropping the HR quite as much. Some people feel significantly better on them, others feel similar, and a few still get fatigue.
Your HR swings (50 → 120 with light activity) can also happen in HCM. When the medication is too suppressive at rest, the body sometimes overcompensates with activity. That’s one reason doctors adjust or switch meds.
Whether to make the change now or wait for the specialist:
Pros of switching now:
– If metoprolol is the cause of your fatigue, you may learn that quickly.
– A trial off the med is reversible and doesn’t close any doors for the specialist visit.
Reasons to wait:
– If your symptoms are stable and not dangerous, some people prefer letting the HCM specialist make the plan.
But since your cardiologist already suggested a supervised trial off the beta-blocker, that approach is very reasonable and commonly done.
Patient experiences vary a lot. Some people feel dramatically less tired once metoprolol is stopped; others notice no difference and then try diltiazem with better results. A few prefer going back to a low-dose beta-blocker. It really is a trial-and-error process in HCM, guided by symptoms, heart rate, and how obstructive your gradient is.
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