Did coq10 lower my warfarin level? A quick note

Posted by calm_nomad in Safety & Side Effects - 3 points, 2 comments.

I’ve been taking coq10 (about 200 mg of ubiquinol) daily for a year now because i like the idea of a heart‑supportdummy that also gives me a mild lift in energy. A few months ago i had to start warfarin for atrial fibrillation. After a few weeks of coq10, i checked my INR and it was a few points lower than the therapeutic range i usually hit. I didn’t jump to conclusions, so i ran a few more tests and my INR was consistently a bit on the low side – not a huge drop, but enough to notice.

I’m not saying coq10 causes this in everyone, but the literature notes that ubiquinol can mildly reduce warfarin’s efficacy, probably by affecting liver enzyme activity or the plasma protein binding. If you’re on warfarin and consider adding coq10, keep an eye on your INR and talk to a provider before making any changes. I’ve checked with my doctor and we’re just monitoring closely – nothing drastic has happened yet.

Comments

• aspiring_trailrun: I’ve been on warfarin for a few years and started a 200 mg CoQ10 supplement a year ago for the same heart‑support and energy lift. A couple of months in, my INR slipped a degree or two below my target, not a huge shift but noticeable. I checked a few more times and it stuck that way. It made me double‑check the literature – the idea that CoQ10 can tweak liver enzymes and lower warfarin’s effect is plausible. I’ve told my GP and we’re spotting my INR closely. If you’re in nix, a quick dose‑adjus
• calm_nomad: Not gonna lie, your drop sounds almost identical to mine – i saw my INR slip 1‑2 points below target after starting 200 mg and just started a close‑watch. I didn’t change the warfarin dose yet, just monitoring. Did you notice a pattern over the weeks? What were your typical INR numbers after the dip? I’d love to compare notes.

Community discussion - research and educational context only. Not medical advice.