Metformin & Vitamin B12

Mar 19, 2019

By: Trevor Shewfelt, Pharmacist at the Dauphin Clinic Pharmacy

Eric played hockey with the Dauphin Bantams this year. In early March, the Dauphin Bantam Hockey team won the Rural "A" provincial championship in Stonewall. The coaches worked hard to prepare the team all year. Like any team, there was drama leading up to Stonewall. But despite injuries, periodic trouble staying out the penalty box and even impending surgeries, the team gelled and played some of their best hockey of the year that weekend in Stonewall. But before championship Sunday, back in our hotel room, Doris started feeling really sick. Faint, dizzy, nausea, head ache. Doris didn't think she would make any games on Sunday. That was terrible news. Because that meant I was getting called up from the minors to do TeamLinkt for her. And I wasn't sure if I was up to the task.

Metformin is an older drug for Type 2 diabetes. Reportedly, the origin of metformin can be traced back to an herbal remedy from the French Lilac back from the Middle Ages. Here are just a few reasons metformin is so great: it can help with weight loss, while nearly all other diabetes drugs cause weight gain; metformin reduces high blood sugar, but is unlikely to make blood sugars go too low; you can keep taking metformin even if you need to start insulin and it is very inexpensive compared to the newer diabetes medications. Most diabetes guidelines agree that metformin should be the first-line medication for Type 2 diabetes. Like all medications, metformin has some side effects. Metformin can cause upset stomach and diarrhea. Because of how metformin is removed from the body, if a patient has kidney disease generally metformin isn't given to them.

Metformin is a great drug for Type 2 diabetes. It is probably the most common medication I dispense for diabetics. I think you could even make a good case for metformin being the best medication for Type 2 diabetes. But, although metformin is awesome, I came across an unusual side effect that I'd never heard of. Metformin can make some people become Vitamin B12 deficient. This interesting side effect gave me a bit of a tingle.

Vitamin B12 does a lot of things in the body. It is usually associated with helping the body get iron out of your food and into your red bloods cells. But B12 also helps your nerves stay healthy. Not enough Vitamin B12, which we call a Vitamin B12 deficiency, can lead to nerve damage. One of the symptoms of that nerve damage can be tingling fingers and toes. Diabetes can lead to diabetic neuropathy. Diabetic neuropathy is nerve damage that can cause tingling fingers and toes. That means it is possible a diabetic on metformin might go see their doctor complaining of tingling fingers and toes, but the doctor might mistakenly write it off as diabetic neuropathy instead of checking to see if the patient's Vitamin B12 level is low.

In a small study of 157 women with diabetes presented at the Society for Endocrinology 2018 conference in Glasgow, Dr Kaenat Mulla from Nottingham University Hospitals and her colleagues found some interesting things. The average age of the subjects was 63.4 years. The most common dose of metformin was 2000 mg per day, and the average duration of drug use was 6.4 years. Sixty-four percent of the subjects had not been tested for a Vitamin B12 deficiency. Almost 10% of the subjects were found to have Vitamin B12 deficiency, but only just over 6% were being treated.

This was a small study. No diabetes treatment guidelines yet recommend routine Vitamin B12 screening. And getting everyone on metformin screened for Vitamin B12 deficiency would cost the health care system money. But it might be worthwhile to have the conversation about a Vitamin B12 blood test with your doctor the next time you see them. Because treating a Vitamin B12 deficiency is often just taking an inexpensive vitamin tablet every day.

I'm always worried that when I do articles about side effect of medications, that people will use that as an excuse to simply stop taking their medications. I hear I'm supposed personalize health information and make it specific, so it sticks. Here it goes. If you are like my friend nick named "Little Bear" and you live North of Fork River and South of Camperville - don't stop taking your metformin. Diabetics on metformin die less often than those who aren't on metformin. Those on metformin seem to get cancer less often than those who aren't on metformin. Metformin seems to increase both the number and quality of years of life of a patient.

If you haven't been to a minor hockey game in 30 years, there are now team communication apps. Among other things, they let parents at the game update who is in net, the score, penalties etc. It is really handy, especially if you have more than one kid playing in different towns on a weekend. On Eric's team, Doris and Lisa Fee have done the score updates most of the year. Now on championship Sunday, I was tasked with trying to type Bantam Hockey play-by-play into my phone. I called Jonah "Joan" a few times. I assigned player of the game to the wrong person, and I relied heavily on the parents around me for who got what goal, assist and penalty. Doris's job is hard. I'm really glad to give it back to her. Regular hockey Dad is all the extra responsibility I can handle.

The information in this article is intended as a helpful guide only. It is not intended to be used as a substitute for professional advice. If you have any questions about your medications and what is right for you see your doctor, pharmacist or other health care professional.


Read more Health Articles

Unite Interactive