Time for injected b12 to be eliminated

[SLM12]

Does anyone have any info around the timescales for elimination of b12 from the body after injection in someone with malabsorption. I have read about a 6 day half-life, but elsewhere people suggest it is 24/48 hours until it is eliminated? My GP won't do injections every other day until no further improvement as per NICE guidelines for those with neuro symptoms and I'd like to be able to give her the reason why this is necessary.

[Nackapan]

I would see another G.p.Or ask then to get advice from a neurologist .

No idea why doctors don't read or go by the NICE guidelines .

What has your doctor offered ?

Have you had a referral depending on what your symptoms are .?

[SLM12 in reply to Nackapan]

I had 5 loading dose in November and was told I should have 3 monthly maintenance beyond that. My symptoms improved (fatigue, tingling, tinnitus etc) but returned after just less than a month (I had low folate at the time of loading, which I didn't know about and so not optimal conditions for loading - I'm now taking folic acid and levels are high again). I am also under the care of oncology (surgery for cancer which removed my terminal ileum, hence the B12d) and I spoke to them last week about it all. They sent an email to my GP asking her to follow the loading guidelines (re-loading on alternate days until no further improvement then monthly thereafter) and she has agreed to re-load BUT only with 5 doses then monthly thereafter. She says they can't offer more than 5 for loading because "that's what they've always done!". Obviously this an improvement on Plan A but not what oncology requested and not what the NICE guidelines state. I've had the neuro symptoms for over a year - with initial loading in Nov they improved but didn't disappear. So I don't really expect anything different this time around. She is referring me this week (but will the consultant be any more informed/sympathetic?!).

[Nackapan in reply to SLM12]

At least some movement.Unfortunately this is not unusual .

Hoping you can push for more EOD .

I had to do that.

It was requested by a neurologist .

Hopefully your consultant will request it in z letter to G.p

At least theve promised monthly after that .

It should be monitored by symptom relief and done gradually so you know what regime you need long term.

Many of us need more than monthly .

Hope you can get it sorted.

I think the time it takes to leave our system varies .

I've read up to 80% gone in 36hrs ,48hrs .

We doo wee put what is not needed .

I eas told once 1mg/ 1ml b1w injection has mostly depleted by a week.

So many times heard on here and told by doctors .

Levels of B12 do have to be kept high to access it . With an absorbtion problem we are totally dependent on what's circulating in our blood stream

[Technoid]

There are different accounts, for example:

(1)

"Peak plasma levels of cyanocobalamin are achieved within 1 hour after intramuscular injection. Within 48 hours after injection, 50% to 98% of the dose is excreted in the urine, with the majority within the first 8 hours."

elsevier.health/en-US/previ...

The source of this information is described as "Cyanocobalamin injection package insert"

(2)

"Biological Half-Life of Vitamin B12 in Plasma"

Two experimental methods derived a half-life for B12 of between 5-6 days.

nature.com/articles/198200a0

[Gambit62 Administrator]

There isa lot of variation in how long B12 is retained in blood. In some patients levels can remain high for years. Unfortunately the studies that found this only measured serum levels and did not look at symptoms. Symptoms depend on how much B12 is getting into cells. Unfortunately serum B12 doesn't measure this,

[Sailinglady]

The resistance to doing more frequent injections for longer may be related to the availability of nursing time to administer the injections. Ask if they will teach you to self administer, then they can prescribe the ampules for you.

If they don't have a protocol for teaching self administration, then ask them to contact the PAS who can probably put them in touch with someone that does.

The half life in the SPC for hydroxocobalamin will have been done in healthy adults, therefore won't necessarily apply to someone without an ileum. The SPC states:

"Hydroxocobalamin is stored in the liver, excreted in the bile, and undergoes extensive enterohepatic recycling; part of the dose is excreted in the urine, most of it in the first 8 hours. It is stored in the liver, excreted in the bile, and undergoes enterohepatic recycling; part of a dose is excreted in the urine, most of it in the first 8 hours."

Where it says enterohepatic recycling, it means the hydroxocobalamin is excreted with bile into the bowl and reabsorbed in the ileum. As you don't have an ileum, this reabsorption will not happen efficiently.

[Nackapan in reply to Sailinglady]

Yes self injection seems the answer with NHS prescriptions.

They talk of nurses time, but HCa's do them on a very low grade so less pay. In the surgery and in the Community .

Immunisations are prioritised as not only needed but a money incentives given to hit targets .

They take longer .

They are not not needed more than B12 in my opinion.

Both are needed .

By giving us appropriate treatment keeps us away from their door and doctors 'time

Obviously everyone has to get tested for everything else as symptoms overlap with other things .

Process of elimination.

Nothing else was found for me to treat.

If B12 treatment was money making . Targets would be set .

Subcutaneous is not licensed for B12 Injections in the UK.

They do work though.

It's clearly printed on the 'German boxes of B12 boxes .

I've been doing this for 6 years now.

My last G.p surgery ( now shut) asked the CCG about Sc b12 injections.

No reply was seen ???

It was suggested on a letter from a neurologist and one g.p decided to sanction them with alot of opposition from 5 colleagues.

Her back was covered by that letter though.

A phone call 'out of the blue ' she decided to prescribe for self injection.

It was a breakthrough .

I'd already bought my own with help from here as anxiety was being experienced about getting my much needed B12 .

I wasn't going back to that dark place of illness/ bedbound alot of us fear .

I really do not see the point of NICE guidelines being produced at a very high cost .

Only to be unread or totally ignored by G.ps !!!

[Bellabab]

You need to know at all this nonsense about limiting B12 injections began as part of the austerity plans by the new government in 2010. There is no scientific or medical reason for it.

[B12life]

this might be a hard angle to argue on.

Read this.

pmc.ncbi.nlm.nih.gov/articl...

Make a one page summary page of top facts that justify injections.

Highlight the facts in the article.

Then use the letter from PAS to submit a letter to your doc.

(Adding it in on min.)

If this doesn't work , get a different doc who will listen or get your own supplies and do injections on your own.