Heart rate slows too much with B12

[Kayledg]

After acquiring a rare reverse side effect from taking gabapentin, I now have skin & mouth burning sensation which is VERY difficult to deal with. After doing research, I found vitamin B may be the answer and taking a large dose of b12 has helped many people with the mouth burning issue. I think it is helping me too, but when I take it, my heart rate seems to drop - 61 bpm -- which doesn't feel right to me. It feels like I need to work harder to get my breath -- like I'm too slowed down.  I feel better when my heart rate is in upper 60s or 70s. Recommended dosing for this condition is 3000-5000 mcg b12 per day. I took 2000 mcg this morning and will probably take 1000 mcg this afternoon. Is there a way I can take the b12 without it dropping my heart rate?  

[gethprime]

Technically that is on the low end of the normal range. Is that your normal resting rate (not the rate during/just after sleep)?