@kathleen1314 I pay attention to your comments which are always based on research and careful thought. That's why I particularly took note when in regards to MK-4 you said "....do not take if you use blood thinners."

I take Eliquis (a blood thinner) but had planned to resume taking MK-4. I'd taken MK-4 and MK-7 for a few years prior to developing afib (2023) but stopped taking both when I started Eliquis. My afib episodes were episodic and each episode lasted several hours. I elected to have a heart ablation in Sept 2025 to try and stay ahead of afib.

I was diagnosed with estrogen-positive breast cancer in the fall of 2024. Based on my age of 75, a high FRAX score of 26%, a status of osteopenia, and now the addition of an aromatase inhibitor (a drug well known to cause damage to bones), my oncologist recommended a Zometa infusion which I had in October 2025.

I hoped to start with an anabolic osteoporosis drug, but was told that was a no-no for someone with hormone positive breast cancer. I did not want to start Prolia so next best option was Reclast/Zometa.

I provide this history to say all my bone health supplements prior to the afib and then estrogen positive breast cancer have been abandoned. I stopped nattokinase and strontium citrate with Eliquis. My wish to resume bone health supplements that I think MIGHT help my bones also seems particularly challenging and limited to food.

I used to make nattokinase but it can interfere with Eliquis so had to stop. I used to also take strontium citrate but think there was a reason I stopped it though have forgotten which drug it might interact with! (main drugs with possible interactions include eliquis, letrozole, kisqali, naturthroid, lyrica) I hadn't even explored resuming MK-7 because I ruled it out with a history of afib.

But MK-4 I held out as my new holy grail. The one supplement I might add. And then I read your brief statement and realized I might be mistaken. I've asked my electrophysiologist who did my heart ablation and my regular cardiologist about taking MK-4 while on Eliquis and neither voiced concerns about it. Now, I'm suspicious that they didn't look into it very far.

I will see another cardiologist soon and will ask her about MK-4 and Eliquis. She specializes in oncology. It will be interesting to see what opinion she has on this subject.

Meanwhile, I presented the issue to Google AI and it echoed your concerns about Eliquis and MK-4. Eliquis is the drug that simply won't play nice with others. I'd like to go off the Eliquis and try and self-monitor my afib but that's definitely going against mainstream advice. My electrophysiologist, though, would support me in trying this. It's just that the stakes are so high if you get it wrong.

If you can cite any of the sources you used to say that you shouldn't take MK-4 if also on blood thinners, that would be helpful. Perhaps the blood thinner they refer to is warfarin rather than the newer class (DOACs - Direct oral anticoagulant) but I fear that's not the case.

If you have the time or inclination to respond to this, much appreciated, but if not, no worries.
Thank you for guiding us with so much useful information!!