What is a loading dose?: I tried to... - Pernicious Anaemi...

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What is a loading dose?

caro43 profile image
17 Replies

I tried to find the answer and I am confused. I have 1 ml vial of methylb12. Is this a loading dose? Thank you

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caro43 profile image
caro43
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17 Replies
Foggyme profile image
FoggymeAdministrator

Hi Caro43. I've just left a reply to your previous post (you may not have seen it yet).

It contains details about the loading doses and also about the regime of B12 that you should be having (also stuff about folate and ferritin).

If you don't find the answers you're looking for, just ask 😀

👍👍

caro43 profile image
caro43 in reply to Foggyme

I didn't understand 6x 1 mlg for 6 days. Can you explain based on my 1 ml vials? Thank you

fbirder profile image
fbirder in reply to caro43

Your 1ml vials almost certainly contain 1000ug (1mg) of B12. As a loading dose you'll want to inject one of those every other day for two weeks.

Foggyme profile image
FoggymeAdministrator in reply to caro43

The ml measurement refers to the volume of liquid the Hydroxocobalamin is contained in. The mg measurement is the amount of Hydroxocobalamin (the drug dose) contained in that liquid.

You do not say how many mg's in the 1ml but if it's the usual dosage, it's likely to be 1mg of hydroxocobalamin (or whatever cobalamin you are using).

The 1ml vial would be the first loading dose of six (you need five more to fully complete the loading doses).

You should then move on to 1ml (1mg of Hydroxocobalamin) every other day, until no further improvement.

The vial or box should state the dose contained in drug quantity (I.e. 1mg) together with the volume of fluid (1mL).

Not sure how clear I've been...if it's like trying see in fog, ask more - and excuse my lack of clarity 😀.

👍👍

caro43 profile image
caro43

oh i thought you meant do it 6x's. I did it twice today. Hopefully that is ok!

caro43 profile image
caro43

I was impatient. shoot.

caro43 profile image
caro43

please tell me I will be ok.

Foggyme profile image
FoggymeAdministrator in reply to caro43

Don't worry....B12 is not dangerous...you will be fine. Any excess will be excreted in your urine.

Doses of 5,000mg X 2 are given for carbon monoxide poisoning - a massive amount compared to what you have.

You may get flushed, or get some spots on your face, but this is something people get occasionally and nothing to worry about.

Hope this reassures you 😀

caro43 profile image
caro43

I am in a total panic about it now. I did it twice today.

caro43 profile image
caro43

Thank you. ok. Hopefully I will just excrete out the excess! Thank you so much. Hopefully it won't keep me up all night!

Foggyme profile image
FoggymeAdministrator in reply to caro43

No....won't have you running all night 😖. You'll just pass the usual amount of urine and won't notice a thing 😀.

Shout up if you need any more help with anything 😀

Foggyme profile image
FoggymeAdministrator in reply to caro43

Forgot to say, some people say that methylcobalamin gives them a headache (an ice cream headache) 😖...but not all 👍

caro43 profile image
caro43

In your reply you wrote 6x1mg every other day for 6 days is the loading dose then 1mlg every other day... I am still confused. Is it 1mlg for 6 days then switch to every other day?

Foggyme profile image
FoggymeAdministrator in reply to caro43

Hi Caro43.

Not quite 😀...

1mg on alternate days (I.e. Every other day) this is the six loading doses, then...

Continue every other day until there is no further improvement in your symptoms...then

1mg every eight weeks.

It's quite confusing because the frequency of the loading doses is the same as the frequency as the 'every other day until no further improvement' bit...

So...if you inject every other day until no further improvement....you'll be getting the right amount.

But...every eight weeks is not enough for some people. When you change to the every eight weeks regime, you may notice that some of your symptoms come back. If they do, this means you need the B12 injections more frequently (lots of people do).

Once you get to know when your symptoms are creeping back in, you'll be able to tailor your B12 injection regime to suit your own particular needs. The aim is to have the injections frequently enough to stop,your symptoms returning.

The frequency of injections to make this happen is different for everyone and you'll get to know you own bodies needs, over time.

Sounds like you're self-injecting so if you need anymore help, just ask.

Most of use have been there and know how scary and difficult it is, especially in the beginning 😀

I think the importance of having good folate levels has been mentioned before? Have you had your levels checked...

👍👍

caro43 profile image
caro43 in reply to Foggyme

yes, they were 17 with a ref. range of >3. I did 1mlg every day for 2 days then 2 mugs today, so yeah I need help! ok, I get it now, so i will start with 1mlg every other day for 6 days to do the loading dose then keep the every other day until symptoms subside- I am praying they do!

Foggyme profile image
FoggymeAdministrator in reply to caro43

Excellent....don't worry...you have it now 😀.

Some symptoms take a while to subside, especially if you have been deficiency for a long time - and some go quite quickly.

So just keep at it and don't despair if you don't feel immediately well - for some it is quick, for others takes a while.

We're also speaking bout folate on your post after this one so I'll 'do' the folate there 😀.

Hope,you start to,pick up,soon x

Gambit62 profile image
Gambit62Administrator

loading doses are doses that are given at the start of therapy to get your levels of B12 up quickly from very low levels. There-after you receive mainentance doses.

Loading regimes vary from place to place and with different forms of B12. In the UK they are hydrooxcobalamin 1000mcg administered 3x weekly - for 2 weeks if no neurological symptoms and until symptoms stop improving if there are neurological symptoms.

Maintenance doses are also 1000mcg.

The frequency is a reflection of how quickly on average the kidneys remove excess B12 from your body - it is quicker the higher the levels in your blood - so it is about getting the best balance between dose and frequency to build levels in your blood up quickly.

And as Foggyme says - taking a lot more isn't going to cause any toxicity - just that it may not be the most efficient way of dosing yourself up because more is going to be lost more quickly if the levels in your blood are higher.

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