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    G6PD deficiency and Metformin
    nikitakev posted:

    is there anybody here who has a G6PD deficiency and takes Metformin? My husband was just diagnosed as a T2 and his doctor refuses to even entertain a different option for Medication even the Pharmacist advises against taking it.
    Everything I can find on the topic strongly suggest someone with G6PD should not take Metformin, I am still arguing with the insurance company to let him see a specialist but in the meantime I am really scared to let take the meds.
    Has anybody been there?
    mhall6252 responded:
    I don't recall this ever coming up on this board. My suggestion is to seek a second opinion. Whether it's a different family practitioner, internist or specialist, you should be able to get another opinion.
    Diabetic since 5/2001
    Follow my journey at
    Smile and the world smiles with you.
    nikitakev replied to mhall6252's response:
    Thanks mhall.

    I have since spoken to an Endocrinologist and he took my husband off Metformin immediately. He also told my husband that a lot of people with this deficiency will develop Type 2 diabetes. He said in his opinion it explains those who are not overweight, are very active and generally eat healthy when diagnosed( like my DH )
    I find it interesting that this has not come up here yet. Metformin is an absolute contraindication when G6PD deficient, it can cause Hemolysis.
    I find it shocking how little his general practitioner knew about this, he tried to blame my DH for not telling him that he has this deficiency (even though he did not know what it is ).
    Every doctor should ask or test for G6PD deficiency before prescribing a sulfonylurea agent for diabetes type 2.
    The endocrinologist also said that people who take Metformin and have really bad side effects are more often than not G6PD deficient.

    NWSmom4g replied to nikitakev's response:
    Nikitakev, Metformin is not a sulfonylurea.
    nikitakev replied to NWSmom4g's response:
    according to it is

    Treatment of patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency with sulfonylurea agents can lead to hemolytic anemia. Because Glyburide and Metformin hydrochloride belongs to the class of sulfonylurea agents, caution should be used in patients with G6PD deficiency and a non-sulfonylurea alternative should be considered. In postmarketing reports, hemolytic anemia has also been reported in patients who did not have known G6PD deficiency.

    and according to

    View G6PD Deficiency Contraindicated Substance Details
    Metformin Formula C4H11N5 Chemical Name 1-carbamimidamido-N,N-dimethylmethanimidamide Category Antidiabetic Hemolysis Risk High - All Those Affected All G6PD Information Chemical Information Notes Reports suggest that Metformin has caused hemilysis in people without known G6PDD.

    my DH took Metformin and had the beginning stages of Hemilysis. Nothing else could have caused it
    laura2gemini2 replied to nikitakev's response:
    According to a pharmacist, metformin is not a sulfonylurea, it is in the drug class biguanide.

    Metformin may be what caused the hemolysis, but that doesnt mean it definitely is in the drug class. Sulfonylureas make the pancreas produce more insulin (drugs like glimepiride and glyburide). Metformin makes your body use it's own natural insulin better, while also making the liver produce less sugar.

    Dont always believe what you read on the internet. While it has a vast amount of knowledge, it doesnt have to be true or accurate to be on there.
    nikitakev replied to laura2gemini2's response:
    Well, I definitely don't believe everything I read online, nor do I believe everything a doctor or pharmacist tells me. I use it at tools in conjunction with my family to determine what is best for us.
    In the case of Metformin there are only a few studies published in medical journals in the world. I have read several European and a few Asian ( although when it comes to anything medical concerning G6PD deficiency I trust Europeans the most, they are simply more advanced in medicine- just my personal opinion and experience.
    My son was diagnosed with G6PD deficiency after a routine doctors appointment in Europe ,my husband was diagnosed years later in the US and not until I printed material from the Internet and showed his doctor, for him to even test him for it. I have yet to meet a doctor in the US who knew what G6PD deficiency is, much less what kind of meds they can not take. When my son had to have an operation I had to sit with his anesthesiologist and tell him that he can not use conventional anesthesia on him because of this genetic defect.
    So I am not surprised that a pharmacist does not know or believe that Metformin is "classified" in the sulfonylurea agent category.
    I now know that my husband reacts to Metformin and we believe it is because it is a sulfonylurea agent drug ,
    I am not a doctor just an RN and I can not give medical advise just share my personal experience.
    laura2gemini2 replied to nikitakev's response:
    All things about the G6PD and studies and such aside, there is no "belief" when it comes to drug classes. It either is or isnt. You cant call the sky green because you believe it to be. You cant call Metformin a Sulfonylurea just because it causes hemolysis in people both with and without the G6PD (according to the one website you cited).

    Think of drug classes like food. Apples and cherries are fruits, so they are both in the "fruit class". They both cause blood glucose to increase. Just because a potato also causes an increase in blood sugar doesnt make it a fruit as well. Sulfonylureas may cause hemolysis, but that doesnt mean that metformin is one just because it has the same side effect.

    Or, think of it as something that causes side effects. I am allergic to Actos. It causes me to swell up. I am also allergic to Avandia because it is in the same drug class. I happen to be allergic to certain spices too, which also cause me to swell up. Just because the spices give me the same side effect as the medication doesnt mean they are the same thing.

    Drugs are classified by what is in them. There is no belief that can change what it is down to it's essentials. There is no grey area.

    I am not allowed to say if I am a medical professional or not per WebMD rules, but my information does come from a professional source.
    laura2gemini2 replied to laura2gemini2's response:
    An easier way to say it.

    All sulfonylureas have sulfur in them (hence the name)

    The metformin molecule is:
    (CH3)2N-(=HN)-HN-(=HN)-NH2*HCL Meformin hydrochloride.

    *No* sulfur.

    Ergo, meformin is not a sulfonylurea.
    nikitakev replied to laura2gemini2's response:
    I really don't want to argue ,
    I talked to 3 different Pharmacist ( CVS, Walgreens and a military hospital pharmacist) in the last 10 days two said it is and one said he does not "believe " it is.

    The CVS pharmacist told me he does not believe Metformin falls into that class.
    Again , just my experience
    auriga1 replied to nikitakev's response:
    Metformin, according to the Physician's Desk Reference (in every doctor's office) and the Health Professional's Drug Guide used in many schools, is a bigunide. It is a hormone synthetic subsitute prescribed as an "antidiabetic" medication. It helps the muscular cells utilize the glucose in the bloodstream much like natural insulin produced in the pancreas.

    Sulfonylurea drugs for diabetes are an entirely different animal. Glyburide, Glipzide, Tolazamide are sulfonylureas which are used to help lower blood sugar by stimulating the pancreas to release more insulin.

    Personally, I would be afraid of those pharmacists who insist metformin is a sulfonylurea.
    hootyowl2 responded:
    Hi Nikitakev,

    What is a G6PD deficiency ? I know the metformin and other diabetic pills I tried ALL made me very sick, even so, it took my doctors about 18 months to put me on insulin. They all mess with one's liver, and I have an enlarged liver.

    Glad you found an endo to take hubby off the metformin, it is nasty stuff.

    brunosbud replied to auriga1's response:
    Concur. Not a sulfonylurea...

    The point is being missed, here. No matter how fragile their RBCs are, a high percentage of T2Ds are anemic from the get-go...

    Majority of T2Ds suffer from all kinds of nutritional deficiencies that can result in anemia and whichever antidiabetes medication one is taking, sulfonylurea or biguanide, either one can increase the risk of anemia, further still. My friend who's a doctor taught many years ago...On a blood test profile, check out hemoglobin and bilirubin levels, first...Then, check everything, else.

    Anemia is no joke.
    hootyowl2 replied to brunosbud's response:
    That is for sure. Chronic anemia runs in the women of my family. My sister almost died once from it, she had to go to the ER and get transfusions. They found she had a bleeding ulcer that time; but we still have trouble with anemia anyhow. I think her hemoglobin was down to 3 or 4 the time she had the ulcer. [she does not have T2>

    brunosbud replied to hootyowl2's response:
    I cringe when I'm out and about and see so many young women, overweight, these days. Its an extremely dangerous way to head into their birthing years.

    Women are are predisposed to pernicious anemia, already...
    When you couple this with, obesity, T2D, iron deficiency, osteoporosis...

    Not good...not good, at all...

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