Metformin Best Practice

[MoB1953]

Diagnosed with T2 in December I immediately changed to low carb diet whilst starting on Metformin 500mg with a regime of half tablet increases every fortnight up to 4 tabs (2000mg). Daily BG testing shows that BG levels stabilised and were well within accepted limits even at 1000mg. Today, as per my GP's regime I have increased my dose to 3 tabs (1500mg).
I've had two recent episodes - trembling / light headed when BG levels dropped below 4.0 so I saw my GP and showed him a graph of my results. My GP wants me to continue increasing dosage up to 2000mg as, he says, this is regarded as best practice management - even though BG levels are stable already and comfortably within published guidelines. He also said that Metformin doesn't cause hypo's.
Having spoken to a couple of friends with T2, their long term dose is 1000mg a day which also prompts me to question why I am being prescribed a higher dose. My goal is to control my diabetes with diet alone.
Can anyone point me in the direction of reading material on accepted best practice dosage for Metformin?

 

[Mike d]

He's your doctor .... having said that, what was your HbA1c reading? Metformin is not all that useful in lowering blood sugars.

If it was me and my time over again, I'd have some serious questions to pose of him. That's one big daily dose

 

[Guzzler]

My HbA1c was 98 on diagnosis and I was prescribed 2000mg (4 tablets) per day, this after an initial starting dose of 1000mg per day for the first week. Metformin does not have a great affect on blood glucose levels even at this dosage and is not prescribed for this reason but to aid the liver.

 

[Mbaker]

You have to decide if what you are being told is sensible, arguments for additional Metformin, your current dose or none at all. When I was first diagnosed I took no Metformin and went from blood glucose readings of over 20 to 16 in one week - even though I did not know what I was doing (still having too many carbs). This 20% drop suggested I could have continued reducing drugless. My Doctor still put me on Metformin (if I wasn't ignorant, I would not have done this).

Amongst other voices, if you asked me direct I would say stick with where you are at worst and then when you are confident consider reducing Metformin by half a tablet (so long as you are not using slow release), seeing where you are until Metformin equals gone - this is my view based on the numbers you are getting already.

 

[MoB1953]

He's your doctor .... having said that, what was your HbA1c reading? Metformin is not all that useful in lowering blood sugars.

If it was me and my time over again, I'd have some serious questions to pose of him. That's one big daily dose

My HbA1c result in December when diagnosed (and before medication and change to low carb diet) was 7.1% I have yet to have a follow up test.

 

[britishpub]

I believe that there are numerous studies that appear to indicate that Metformin has an optimal dosage at 1000mg daily, and taking a larger dose than that is not necessary.

@Brunneria has posted on this subject in the past.

 

[MoB1953]

I believe that there are numerous studies that appear to indicate that Metformin has an optimal dosage at 1000mg daily, and taking a larger dose than that is not necessary.

That's useful to know. I get the diarrhoea side-effect (even after approx 3 months) and each time I increase the dose, it only makes things worse. All I can find is info that says 2000mg is the usual maximum prescribed limit.

 

[MoB1953]

You have to decide if what you are being told is sensible, arguments for additional Metformin, your current dose or none at all. When I was first diagnosed I took no Metformin and went from blood glucose readings of over 20 to 16 in one week - even though I did not know what I was doing (still having too many carbs). This 20% drop suggested I could have continued reducing drugless. My Doctor still put me on Metformin (if I wasn't ignorant, I would not have done this).

Amongst other voices, if you asked me direct I would say stick with where you are at worst and then when you are confident consider reducing Metformin by half a tablet (so long as you are not using slow release), seeing where you are until Metformin equals gone - this is my view based on the numbers you are getting already.

Thank you. I feel that questioning what I now eat, portion control and adopting a low carb low, GI diet has done a lot by itself. I am not comfortable about taking yet greater doses of Metformin without being convinced that there's a robust medical case for doing so particularly as BG levels are stable and within recommended limits. It's a conversation I need to have with my GP on my next visit.

 

[Robbity]

I get the diarrhoea side-effect (even after approx 3 months) and each time I increase the dose, it only makes things worse. All I can find is info that says 2000mg is the usual maximum prescribed limit.

Are you taking the standard metformin or the slow release version? The SR one should hopefully help avoid any issues with diarrhoea, so if necessary ask to change - you shouldn't have to put up with such issues for so long.

It might help too if you're reducing the carbs in your diet, as starchy food is known to sometimes cause such problems in combination with metformin. See http://www.phlaunt.com/diabetes/14045911.php and scroll down to "Side Effects
Gastric Distress". But the whole page is worth a read.

Robbity

 

[Bluetit1802]

My HbA1c result in December when diagnosed (and before medication and change to low carb diet) was 7.1% I have yet to have a follow up test.

Your HbA1c was not very high on diagnosis. Mine was 7% (53mmol/mol) and medication was never mentioned and hasn't been since. I think your GP is being a bit over generous with it. Imagine if your levels began to deteriorate .... what would he do then? He has already given you the maximum dose of Metformin so would have to move on to stronger drugs. With a lower dose of Metformin now (or even none at all initially) he has the option to prescribe it if and when your levels do get worse (which hopefully will not be the case)

 

[MoB1953]

Are you taking the standard metformin or the slow release version? The SR one should hopefully help avoid any issues with diarrhoea, so if necessary ask to change - you shouldn't have to put up with such issues for so long.

It might help too if you're reducing the carbs in your diet, as starchy food is known to sometimes cause such problems in combination with metformin. See http://www.phlaunt.com/diabetes/14045911.php and scroll down to "Side Effects
Gastric Distress". But the whole page is worth a read.

Robbity

I've asked GP to prescribe slow release and he has agreed. I pick up the script today. Will give your page link a thorough read. Thanks

 

[Resurgam]

I was put straight onto Metformin and a statin, but was so unhappy with the side effects that I stopped taking it after 5 weeks.
If you are suffering the usual side effects then your feelings of light headedness could possibly be due to the loss of water and electrolytes combined with a low intake of food and drink.

 

[MoB1953]

Your HbA1c was not very high on diagnosis. Mine was 7% (53mmol/mol) and medication was never mentioned and hasn't been since. I think your GP is being a bit over generous with it. Imagine if your levels began to deteriorate .... what would he do then? He has already given you the maximum dose of Metformin so would have to move on to stronger drugs. With a lower dose of Metformin now (or even none at all initially) he has the option to prescribe it if and when your levels do get worse (which hopefully will not be the case)

That's exactly how I see things. I've had the lifestyle wake-up call, I'm now being sensible, reading heaps at this website which is so much better than any I have found here in Oz, and following recommended guidelines - except the one I received at a diabetes seminar last week at the local hospital which said that readings within 10 mmol/L were fine!) and my aim is to manage this with diet alone in the future.

 

[MoB1953]

I was put straight onto Metformin and a statin, but was so unhappy with the side effects that I stopped taking it after 5 weeks.
If you are suffering the usual side effects then your feelings of light headedness could possibly be due to the loss of water and electrolytes combined with a low intake of food and drink.

You are right. Part of the problem is that I now live in Sydney which has had its warmest summer on record. I've been playing golf regularly in up to 40+ degree temps and although I drink up to 3 litres of water, twice I've begun to feel a hypo coming on. A few sugary pastilles and a snack and I feel much better and, having had heatstroke a few years ago, I know the difference.

 

[Mellaspirit]

He's your doctor .... having said that, what was your HbA1c reading? Metformin is not all that useful in lowering blood sugars.

If it was me and my time over again, I'd have some serious questions to pose of him. That's one big daily dose

Get 2nd opinion.

 

[Bluetit1802]

@MoB1953

Doctors can only advise, and can only offer medication. They cannot make you take it. That decision is entirely yours. Take the tablets or leave them. It is up to you.

 

[MoB1953]

@MoB1953

Doctors can only advise, and can only offer medication. They cannot make you take it. That decision is entirely yours. Take the tablets or leave them. It is up to you.

You're right of course.

 

[MoB1953]

@MoB1953

Doctors can only advise, and can only offer medication. They cannot make you take it. That decision is entirely yours. Take the tablets or leave them. It is up to you.

You're right.