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Date of last update: 9/5/2017.

Forum Name: Pharmacy & Drug Topics

Question: Metformin(Glucophage) contraindication

 MiBo - Wed Mar 30, 2005 6:11 am

Here in Germany I find one contraindication to metformin ,saying :
Reduction diets with less than 1000Kcal/female or 1400 Kcal/male.
in connection with the risk of lactic acidosis (LA) ,
This I only can locate in germanspeaking countrys , my searches gave no such results
in the rest of the world .Even the fda does not mention it in their 60 page document on metformin (Glucophage) .All the other contraindications and warnings are literally equal.

I wonder if it is realy true,that the above contraindication (hypocaloric diet) is missing in US ,and if someone knows about a possible background to this?

I know their are many studies suggesting their is only very little ,if any ,risk to LA
with metformin when prescribed as labeled.

My background to this is that I´m on a low carb diet since three weeks now , which lowered my BG from over 200 to around 140 now without further medication.
Nevertheless I thing it is to high ,and find strong arguments that I could benefit a lot from
a (maybe low-dose) medication with metformin.
This kind of diet and its benefits are not yet very well known over here ,in fact the absolut opposit (eat 60% carbs and low fat) is told to the diabetes patients .
I have problems in getting metformin prescribed, for the doctor assumes that the low
carb diet is hypocaloric ,where in fact it is hypercaloric.

Kind Regards,
 Rhonda P, CEP - Thu Mar 31, 2005 8:30 pm

User avatar Hello,

Metformin decreases the absorption of carbohydrates through the intestines and it reduces the production of glucose by the liver so if you aren’t consuming enough carbohydrates your body can’t get them and we need carbs to make energy to live. You can see the whole break-down if you look up "carbohydrate metabolism" online. Blood and kidney function tests need to be done periodically to make sure the liver and kidneys aren’t being damaged. Metformin is mostly expelled by the kidneys so in some cases LA levels may raise with the use of Metformin (Glucophage) in people whose liver or kidneys aren’t working well, who have multiple medical problems, congestive heart failure or take multiple medications.

Lactic Acid is an acid produced by the cells during a chemical process in the body that does not require much oxygen. It is the result of the breakdown of carbohydrates for energy when the oxygen level in the body is low. Too much lactic acid causes muscle cramps.
 MiBo - Fri Apr 01, 2005 6:55 am

Thank you for your reply,
As I mentioned ,I´m trying to loose wheight with a "low-carb" diet . The Energy to live is
in this case made from fat ,a process called Lipolysis/Ketosis(benigne).
This is normaly avoided in healthy (slim) people ,as fat is an important energy storage ,but with obesiv people there is a great amount of redundant fat available.
I know many people in the US and worldwide ,doing this diet who gained a better health
(improved diabetes , weight loss etc.) through it.
But this was not the core of my questioning, it is about if someone could confirm
that the contraindication : ketonaemia, starvation diets or similar
are not being mentioned in the informations (US) doctors use to decide if or not to
prescribe metformin.
Is there any way for you to check this?

Kind Regards,
 Rhonda P, CEP - Fri Apr 01, 2005 11:18 am

User avatar Hello,

Well, I'll try this, we'll find what you need if we keep looking.

Ketones are what are produced when the body breaks down fat for energy; this is converted over in your liver. When your body is producing ketones and using the fat for fuel it is ketosis. Ketones are acidic molecules and your body doesn’t like acid so it dumps it into your blood to be disposed of out your kidneys.

Diabetics can have too much sugar in their blood. This causes the blood to become acidic and ketones to build up causing a condition called Ketoacidosis. This is a very dangerous state to be in. You can use a ketogenic diet to lose fat weight but you need to be monitored by your Health Care Provider and your sugar levels need to be kept stable.

Metformin is excreted through your kidneys; if they aren’t working right or are diseased you will have a build-up of medication, ketones, lactic acidosis and urea in your blood.

Maybe the Physicians Desk Reference has more information in it for you.

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