I am sadly self diagnosed as my B12 levels came back in the low but normal range and GP was not interested despite exhibiting a large array of typical symptoms, some quite severe, and a very high MCH result.
I decided to self-inject and after feeling worse following the first loading doses, gradually started to feel better after 6 months. This was 3 years ago.
I am and always have been very active and have prior to self diagnosis taken part in triathlons and half marathons. Exercise is a big part of who I am and needed for my mental health. My exercise regime is more than ever highly affected by my injections. 2/3 days after a dose, I can go on a 10k run and feel ok. I do hiit classes and feel I can give my whole. By week 4, I am out of breath just walking up the road, and almost pass out half way doing that same hiit class I do 2 or 3 times a week.
My question is: does intense exercise speed up depletion? In which case, is it ok to just inject when I just reach that stage of feeling...totally depleted, which at the moment is around 4 weeks? I'm 50 years old.
My other question is does it matter that I don't have a diagnosis? My GP half heartedly agreed to do an active test but I know it can only be done after coming off any B12 for 4 months and this prospect feels me with dread as I know I would end up very poorly again, most likely having to take long term sickness leave from my job. Are there any other reliable tests that can be done whilst in B12 (if only to be done before a new dose)?
Sorry for the longer than intended post. Thanks
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I found that I could not last more than 4 weeks on hydroxo-cobalamin injections? When I moved from UK to USA , I had to switch to cyano-cobalamin and can only last a week. I actually have vials with rubber stopper (and not ampoules which break open) so I can split my weekly in half and not waste (pee away) any excess if I took the whole thing weekly.
No, exercise cannot increase our body's demand for B12. Any more than it can increase your need for zinc, phosphorus, sulfur or any of the other things involved in the same reactions as B12.
It sounds like you need to inject more often.
Ideally you want to find a frequency where your symptoms are just kept at bay. Try injecting once a week. If you don't hit any deep troughs, try every fortnight. Keep increasing until you start to feel knackered again.
There's no desperate need to have a diagnosis. There's no reliable test for Pernicious Anaemia (which is almost certainly what you've got).
I'm quite surprised to hear that exercise doesn't increase our body's demand for B12. I realise that any change in demand of elements in a chemical reaction would be proportional but I would have expected the overall rate to increase for all the elements, which is why tennis players spend half their breaks eating bananas.
The reason I ask...apart from general curiosity...is that when I was struggling along with the prescribed 12 weekly injections, I felt much better when I broke my ankle and was unable to do any exercise for weeks. Then when my ankle got better, I started training but almost immedietely found my general health deteriorated. I'd get hit with flue like symptoms which would last three to four days every time I tried.
Thank you very much. I'm a bit nervous injecting more often without clinical expertise but I can see some do so weekly here without negative consequences.
Can I ask whether we know some can go 3 months whilst others it 2 week?
Nackapan, can I ask why you have become exercise intolerant?
Thank you for your advice on the Intrasic factor test. I'll give it a go.
I'd like a diagnosis firstly because I also.suffer from a very rare genetic disorder and experts could be interested as to whether there could be a link.
Also I expect it is a condition that falls under the disability act and this could potentially help in making a request to reduce my working hours.
Why can some go three months, while others need it every other day?
Nobody knows. The Pernicious Anaemia Society are involved with some research looking that people who need 3 monthly, people who need it more frequently, and people who don't need injections at all. They did find differences in the microbiome of the frequent injectors compared to the other two groups. But that may be because they inject that often.
More B12 into the body means more B12 excreted in the bile. If some types of bacteria find B12 especially yummy then those will thrive under those conditions.
I don't think they found too many bacteria, or any that wouldn't be expected. But they found more of some, and fewer of others, than in the other two groups.
I became exercises intolerant as was initially bedbound .
Had vertigo fir the very first time Had to get walking again.
I now suffer from proper fatigue
I've tried pushing through...not good
I try pacing but really diesnt work at the moment.
Ive tried riding my bike that I rode for over 5o years.
To my delight mg balance was fine.
Have a vestibular disturbance (was told by a neurologist)
So weak .
On getting in afer many triex over weeks. My head symptoms were awful. And dumisturbing.
When I try and walk uo a slight incline or further than 3/4 mile. It feels like my hkasses are clamped ljje metal tk my head head pains and weakness . Them I stagger .
I'm really sorry low B12 had some an impact on you. It is hard when physical activity is such a large part of your life. I suffered from vertigo and poor balance before starting on b12 and it was horrible.
I think the simple answer is that you need to inject more often.
I’m fairly active and cycle up to 200 miles a week but when first diagnosed and on the injection regime given by my GP (one every two months) my cycling ground to a halt. My GP was better than many and allowed a monthly injection which improved matters a lot. Nevertheless, I was still finding that I was good after the injection and would then tail off in the week or two before my next injection.
I then took matters into my own hands and injected weekly and almost felt better but I still was good for a few days post injection and then would tail off.
For the last couple of years I’ve injected twice a week and this suits me perfectly. I’m no longer up and down but live life (and cycle) on an even keel no matter when it is in the week.
This is a question that I was wondering back at the start.Sports have always played a large part in my life. I run, cycle and compete at badminton but when I first had my loading doses I felt a real boost in fitness and managed to reduced my parkrun 5k pb. Of course it wasn't in fact a boost...just a quick return from low energy levels...it's incredible how insiduous low B12 can be!
Then after a year of 12 weekly injections, it was like my reserves had depleted and I was surviving from injection to injection. I did keep running and doing weekly parkruns and I started to notice a trend. At about 6-8 weeks I would really start to struggle and it would go downhill until my next injection...then after treatment, it would take me a couple of weeks to regain any sort of fitness, I'd have a couple of good weeks then start going downhill again.
Then I'm afraid I just kept getting worse until it was taking me about 7 or 8 minutes longer to run 5k, I'd need a sleep when I got back home and I would suffer badly with lactic acid for days after any exercise.
Now I self inject weekly (though I am experimenting with pushing it out to two weeks) and after a couple of years of doing this I finally feel like I can push myself most days again and go for a run in the morning and feel better for it rather than the day being a write-off.
Personally I wouldn't come off B12 for any tests. It does sound as if you need it. When I was getting 12 weekly injections I really felt the effects of the injections. Now I regularly inject and I barely feel any effect which makes me think my levels are now at a reasonable level.
May I ask out of curiosity what your 'normal' B12 levels were?
Thanks for sharing your exoeruence. The account of your experience is exactly how I feel although I am finding the benefits of the injections after only 2 days.
My levels were 303.
The consensus is that I need to inject more often. My worry was that by doing so it would trigger a dependence and make me need it more and more often but it sounds that it is just what my body needs and for some, it is weekly or every other week.
When I was first diagnosed with PA I began a journal to track my symptoms. It really did help me to understand how frequently I needed a B12 injection. But I also noticed that whenever I was unusually busy or dealing with stress or EXERCISED a lot, my PA symptoms increased. There is definitely a pattern. I now know to increase my injections when I need them and rest more frequently. As a formerly very active person, it has been hard to learn to slow down. But it’s worth it. Wishing you the best.
Thanks for sharing this. It's also been my feeling. I never used to count the weeks, just knew when I was getting low as breathlessness and feeling my body weighted twice took over and then would think back when I last injected. And yes, it does seem that the more intense exercise I do during that period, especially running, the quicker I seem to run out.
You will know that you are injecting frequently enough when you don’t feel the need for an injection because of symptoms. You will just always feel normal. I had a negative IF test while receiving B12 injections but that test doesn’t give a definitive diagnosis of PA and no such test is available. It’s safe to say that if you are symptomatic and B12 injections help you, then you’ve got your answer. If you’re not low in B12, then you won’t feel differently after an injection. Frequency is determined by a schedule that keeps symptoms at bay. We would all love to know why some need more frequent injections that others but that’s just the way it is. B12 is water soluble, no risk of overdose. Good luck!
Thank you very much for this. After years of managing the symptoms of low B12, you forget that normality is how you feel after an injection, not when you need one.
I mentioned to a gp once about how different I felt after an injection compared to before and his response was that it was expected and everyone would because it's a stimulant. But I looked it up and saw that it wasn't a banned substance for athletes, so surely if it had such a positive impact on performance as it does for me on everyone, it certainly would be.
As an asthmatic, I've also discovered that breathing is a stimulant. I feel so much more energy and lively when I'm able to breath and I can run so much faster. Should be banned!
When I was low on B12 I could really feel the effects of the injection. Now I'm self injecting regularly I don't notice any boosting effect which I take to mean that I'm not allowing the levels to go low enough for there to be a shortage.
I realize this is an older post and I hope that you have increased your doses by now and found some relief. Everyonce awhile I get on here and search for "exercise" on this forum as I experienced a similar scenario as you and didn't find much information out there while I was going through it.
My testing at 43, was messed up at the beginning, but it was pretty obvious that I crashed down pretty low on B12 as I had a lot of symptoms & losing 10# in a couple of weeks caught my doc's attention that it was indeed B12. It was a long road, but I ended up injecting on my own as well. I am a long distance open-water & pool swimmer & swim competitively & dapple in cycling & variety of other activities.
When I started injecting I did the research and did the loading phase of SI everyother day expecting to just do the two weeks. But whenever I backed off between injections my tingling in my hands/feet & tinnitus would return. At times I've been able to cut back to x2/week, but whenever my activity level is up for a bit either distance or just harder workout phases, I'll notice I'll need more B12. I've done the research and if we're not B12 deficient it won't help our performance. So any benefit performance-wise from supplementing is just because we're deficient, where on the other hand if we're getting extra our body eliminates it. As far as banned substances, B12 is fine, but I think there is a clause about IV's. I heard a rumor that swimmer Ryan Lochte's ban was from getting B12 as an IV drip. If the rumor was valid, it was doubly silly of Lochte as afore mentioned it could have only helped him performance-wise if he was legit deficient and two, he should know the IV rules.
Hope this message finds you at a better spot than where you were 5 months ago!
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