Hi all, I've been on Hydroxocobalamin injections for 5 years, I'm a very keen cyclist and ride almost every day, sometimes up to about 80 miles, averaging at the moment 170 miles per week.
I've just had to self inject for the second time due to the Covid crisis and my GP not allowing anyone on the premises!
I'm on 3 monthly injections, but rarely do I last that long, suffering fatigue for a few weeks before the injection is due.
Does anyone know whether my exercise is burning up the B12 earlier than it should, or does it not affect this?
I'm considering buying extra Hydroxocobalamin to inject myself if it will help and I can find a reliable source.
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CyclingPete
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I’m not sure of the answer to whether or not exercise uses up B12. It’s up for debate going by answers to the same question in a recent post.
I think the important point is how often you need to inject to feel fit and well. If you’re struggling on 3 monthly then the answer is more often than that! Guidelines say injections should be given every 2 or 3 months so you’d be justified going to your GP to ask them to up the frequency.
I cycle a similar mileage to you but wouldn’t be getting out of bed on 3 monthly injections! My GP initially allowed 2 monthly and now monthly. However, even that isn’t enough and I self inject twice a week.
If I leave a longer gap between injections it’s not just my cycling that suffers. I find it hard to function and string a sentence together.
Thanks for the reply, I've just ordered some Hydroxocobalamin to self inject, I was going to try every 6 weeks to begin with and see if I can get by on that, once it begins to work I have more than enough energy for the middle few weeks of my current 3 monthly cycle, it's the couple of weeks before and just after I have the injection that I struggle with. I just sleep all the time and cannot motivate myself.
I find that if my injection is delayed I suffer in a similar way (albeit on a shorter timescale given my frequency). However, I’ve been on twice weekly for a couple of years and find I no longer have peaks and troughs and I think this shows that it’s the right frequency for me.
I’d be interested to hear the answers to this question. I used to be a keen runner and would really like to take this up again however I’ve been concerned I might make myself worse.
I found that building up to my previous cycling levels after being diagnosed with PA took a couple of years. I had to build up slowly, never exhausting myself and always allowing plenty of recovery time. If I pushed through my limits I went backwards rather than forwards.
I got there in the end although I still find it necessary to stay within my limits and allow for adequate recovery.
I hope you will too if you take a softly softly approach!
I tried to push through and it back fires. Slowly slowly is the answer. Tour body needs time to recover then get back muscle and strength. Gentle pysio good .
From my cycling experience I'd say you have to give it a go, I've only ever felt positive results from exercising, I push myself very hard and don't feel that any harm is being done, I just ease off when I hit my no B12 left wall! I take it steady for those few weeks then get back into it as soon as I can.
I went for a longer walk too soon last year and ended up with a 6 day migraine.
People tell me to push through but I know my body cant do it at this time.
It is not good for everyone with this condition. But then I've never managed to get to 3 months between injections either.
It sets me back big time. I've havinv to learn new skills . More patience. More pacing (not in my nature) my toleration of pain has gone up. That was pretty good anyhow
I'm stil waiting for a symptom free day.
Hoping tour nes regime ketosis tih on a good level.
Hi Stacy I am a runner with P. A and was having six weekly injections and feeling really tired one week before they were sue. No have monthly injections and been able to increase my running feeling better for it
B12 is used as co-factor in the Krebbs cycle - which is the one that releases energy in the cells - but I believe that doesn't necessarily mean it is used up. However, I find that a lot of physical activity does leave me feeling in need of B12.
Very few people actually manage to make it to 3 months so its more likely that for you 3 months is just too long a period between injections anyway.
Suggest you keep a diary of symptoms and use that to decide the frequency of your injections.
This is my experience - I now inject weekly. I don’t cycle through distances you do but I run 3 times a week and very quickly found that the more I trained the quicker my symptoms returned.
My GP told me it was nonsense - I’d already gone from 3 months to 8 weekly injections and then monthly. I feel grateful as I know a lot of people on here have really horrible symptoms that seem very hard to manage. I am lucky that I can stay on top of things with weekly injections, and it’s good to know I can increase that if I want to. Before lockdown I was training for a marathon and was managing with my weekly injections. Hopefully you’ll find an increase in jabs really helps and you’ll settle on a routine that works for you.
I’ve also, when I’ve felt particularly bad, given myself 5 loading injections over ten days just to give that boost you get when you first start treatment. That might be something to consider as well.
Purely anecdotal; but having taken what we thought was enough B12, plus a safety margin, on a three-month world cruise, we found that the increased activity was burning it up more quickly.
(And we were very pleased to be able to just wander into a pharmacy in Australia and buy some more without any fuss or paperwork, showing perhaps that the UK could do this, as the NHS doesn’t seem to meet our needs).
Exactly, I don't get the point in EU rules myself, when I can order online from Germany without any problem, but we need a prescription here.
Yes, I'm a runner, running about 150km a month. I inject once a week. Good luck 🚴♀️🚴♀️
I've been on B12 injections for over a decade but was diagnosed by an endo who said the guidelines for treatment were snatched up out of the air no science to back them up, said I should have monthly jabs, I'm a runner and monthly wasn't enough self inject weekly and have no symptoms, well ok a few the endo I saw renowned in his field!!
I'm a fairly high level athlete doing a lot of hiking and mountain climbing. I can't make 3 weeks without a shot. I've experimented and tried. Somewhere at about 18 days (remarkably consistent) I lose my appetite, I get a weird vibration type sensation while trying to fall asleep, my hands, calves and feet start twitching, I start to have a hard time saying certain words, and I feel like curling up into the fetal position on the couch and balling like a baby. (and actually have sorry to admit). All of this remarkably clears up a day after a shot. I self inject at home and was just trying to figure out what was best for me. Since I'm very new to this (6 months in since symptoms quite suddenly showed up), I think I'm just going to do the twice weekly thing for a year since I did have neurological symptoms then maybe experiment again at that time.
Sorry I thought I replied to you already, I know about curling up on the couch and sleeping, that's my world for now, I'm starting to feel a little better today, 7 days after my injection.
Just to round this off if it may help anyone else, I managed a 73 mile ride on Sunday 2/08/2020 everything went well and I feel as well as I did before my sudden slump, so that was 9 days after my injection.
Thanks to you all for your input, it's been extremely helpful.
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is anyone familiar with this pharmacy? 
Which cobalamin should I buy??
Self injecting Hydroxocobalamin subcutaneously
Hydroxocobalamin IM Injection 
