Metformin criteria

[mm93fm]

Hi,

I wanted to get some advice about how to convince my GP to prescribe me metformin

I was diagnosed with Type 2 diabetes last April. Then I went to live abroad for 6 months. I managed to get my HbA1c down to 6.4% through exercise and weight loss but on retinal screening I had some background retinopathy. So a doctor started me on metformin 1g a day. My last HbA1c in March 2020 was 6.1% (on metformin.)

Now back in the UK for good, I approached my GP to get prescribed metformin. He is saying that a HbA1c of 6.1% or 6.4% even does not qualify for metformin. I'm booked in for repeat bloods next week and then we'll see if I need metformin.

They want me to have a documented HbA1c above their arbitrary criteria of 6.5% or something so they can justify prescribing it, even though it's actually a really cheap and safe drug. My thinking is that I don't want to come off metformin, let the HbA1c rise to 7% or whatever, then get metformin in 6-12 months' time. It doesn't make any sense: my HbA1c is controlled because I am on metformin!

When I monitor my sugar levels on metformin I can really see a benefit. It means I can have the odd treat and it can "absorb" that carbohydrate load without sugar levels spiking.

So... any tips on how to convince my GP that metformin would be a good idea?

Thanks!

 

[JoKalsbeek]

Hi,

I wanted to get some advice about how to convince my GP to prescribe me metformin

I was diagnosed with Type 2 diabetes last April. Then I went to live abroad for 6 months. I managed to get my HbA1c down to 6.4% through exercise and weight loss but on retinal screening I had some background retinopathy. So a doctor started me on metformin 1g a day. My last HbA1c in March 2020 was 6.1% (on metformin.)

Now back in the UK for good, I approached my GP to get prescribed metformin. He is saying that a HbA1c of 6.1% or 6.4% even does not qualify for metformin. I'm booked in for repeat bloods next week and then we'll see if I need metformin.

They want me to have a documented HbA1c above their arbitrary criteria of 6.5% or something so they can justify prescribing it, even though it's actually a really cheap and safe drug. My thinking is that I don't want to come off metformin, let the HbA1c rise to 7% or whatever, then get metformin in 6-12 months' time. It doesn't make any sense: my HbA1c is controlled because I am on metformin!

When I monitor my sugar levels on metformin I can really see a benefit. It means I can have the odd treat and it can "absorb" that carbohydrate load without sugar levels spiking.

So... any tips on how to convince my GP that metformin would be a good idea?

Thanks!

I hate to break it to you, but metformin doesn't do anything about what you eat. It never has. Metformin keeps your liver from dumping glucose, lessens the output with up to 75%. It may make you feel less hunger as an aside, but that's it, that's all it does when it comes to diabetes.

If you want to reverse the retinopathy, Metformin isn't really going to do much of anything about that, but a change in diet will. https://josekalsbeek.blogspot.com/2019/11/the-nutritional-thingy.html might help a little.

That said, while you can't outrun a bad diet, I do believe the exercise and weight loss made the main difference, not the met. Hard as it is to believe sometimes.... We do actually can get some stuff done without medication. Can you try and believe you actually made the difference yourself?

 

[Rachox]

I am on Metformin, I was prescribed it on diagnosis in May’17 when my HbA1c was 70 (8.5%).With low carb diet, self testing and Metformin my HbA1c was down to 36 (5.5%) within four months. I have continued on Metformin since diagnosis and my GP is happy to continue prescribing it so I don’t believe there are any criteria “to qualify for Metformin” with regard to HbA1c level. As @JoKalsbeek says Metformin only contributes a tiny amount to reducing blood sugars and therefore preventing complications. Reduction in carb intake has a much more profound effect.

 

[Daibell]

Hi. Have a look at the NICE Managing Blood Glucose for Type 2. It talks about aiming for an HBa1C of 48mmol (6.5%) which is the point at which diabetes is diagnosed and starting Metformin if above. I have to agree with the GP that you don't really need Metformin unless the right (low-carb) diet doesn't hold your HBA1C BS at or below 48mmol.

 

[mm93fm]

@JoKalsbeek My problem is that I find it really difficult to control what I eat, that's the reality. The lifestyle modifications such as diet and exercise are a real struggle for me. I am trying to cut down carbs and keep to an exercise plan, but I don't always manage. I crave carbohydrates, even after a year. An oral medication like metformin covers me for the times I slip up. I'm not perfect. If taking a tablet helps with overall sugar control even a little bit, it's worth taking it (if the side effects are manageable and the cost is not too great).

@Daibell It is really difficult for me to sustain that low-carb diet, and my HbA1cs are teetering in the 6.1-6.5 range, even with metformin. So to me it doesn't make sense to come off it, especially considering it costs the NHS just £2 for a month's supply.

 

[HSSS]

An oral medication like metformin covers me for the times I slip up.

But it doesn’t. It does not work on the carbs you eat. It works against liver dumping glucose when the liver thinks you need it (ie when you are lower - for example after an overnight fast it reduces the dawn phenomenon a little) which won’t be when you’ve “treated” yourself.

 

[Brunneria]

NHS doctors work to a treatment protocol for T2 diabetes, which lays out a clear pathway for the prescription of Metformin as a first choice (if tolerated) when diet and lifestyle choices fail, and when blood glucose is high enough. This then progresses through additional medications, up to and including insulin when/if appropriate.

have a look at this doc which sets the pathway out.
https://bnf.nice.org.uk/treatment-summary/type-2-diabetes.html

This looks like the relevant paragraph:

Type 2 diabetes should initially be treated with a single oral antidiabetic drug. A target HbA1c concentration of 48 mmol/mol (6.5%) is generally recommended when type 2 diabetes is managed by diet and lifestyle alone or when combined with a single antidiabetic drug not associated with hypoglycaemia (such as metformin hydrochloride). Adults prescribed a single drug associated with hypoglycaemia (such as a sulphonylurea), or two or more antidiabetic drugs in combination, should usually aim for an HbA1c concentration of 53 mmol/mol (7.0%). Targets may differ and should be individualised and agreed with each patient.

So it looks as though your doc is following the standard protocol that if you hit the target of 6.5 (48mmol/mol) or below, without having a medication, then there is no need to prescribe Metformin.

Those who start higher, and use Metformin to get below the cut off of 6.5% can make the argument of staying on the drug because it helps them stay on (or below) the cut off.
Those who achieve an HbA1c below the cut off, through diet and lifestyle, without Metformin, are seen as not demonstrating a need for the drug.

Obviously, opinions differ on this! However, if your doc chooses to adhere to the national NICE protocol, s/he is not being ‘arbitrary’, they are doing their job as instructed by NICE (and avoiding spending NHS money on a medication not considered necessary), according to your HbA1c results.