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As a type 2 diabetic, you’ve probably heard of Metformin, or you might even be taking it yourself.
Metformin (brand name “Glucophage” aka “glucose-eater”) is the most commonly prescribed medication for type 2 diabetes worldwide…and for good reason. It is one of the safest, most effective, least costly medication available with minimal, if any, side effects.
There are always lots of questions around Metformin – how does metformin lower blood sugar levels, does metformin promote weight loss or weight gain, will it give me side effects – and lots more.
Today we’ll hopefully answer some of those questions.
How Metformin Works
Metformin belongs to a class of medications known as “Biguanides,” which lower blood glucose by decreasing the amount of sugar put out by the liver.
The liver normally produces glucose throughout the day in conjunction with the pancreas’ production of insulin to maintain stable blood sugar.
In many people with diabetes, both mechanisms are altered in that the pancreas puts out less insulin while the liver is unable to shut down production of excess glucose. This means your body is putting out as much as 3 times as much sugar than that of non-diabetic individuals, resulting in high levels of glucose in the bloodstream.
Metformin effectively shuts down this excess production resulting in less insulin required. As a result, less sugar is available for absorption by the muscles and conversion to fat. Additionally, a lower need for insulin slows the progression of insulin resistance and keeps cells sensitive to endogenous insulin (that made by the body).
Since metformin doesn’t cause the body to generate more insulin, it does not cause hypoglycemia unless combined with a sulfonylurea or insulin injection.
Metformin is one of the few oral diabetes medications that does not cause weight gain and often people note a slight weight loss (although this is not its main action and not everyone experiences weight loss).
While the mechanism for this is not clear, it may be the result of less gluconeogenesis (making glucose) in the liver and/or decreased food intake, likely caused by increased satiety (ie. curbing appetite).
The Downside of Metformin
Despite its perks, there are some precautions to take when starting Metformin.
The main side effect is gastrointestinal (GI) upsets.
Unfortunately Metformin can cause nausea, stomach pain, bloating, diarrhea, and other GI upsets in about one third of people. The good news is that this generally goes away within a couple days or 2 weeks at most.
This GI upset is simply the body adjusting to the medication and in most cases, incrementing slowly per physician and pharmacy recommendation will help to minimise upset. It also helps if you take it at the same time daily with meals.
Be aware that poor blood sugar control itself (both high and low) can also cause GI distress, so optimizing your diet is key as well. If symptoms haven’t waned after a week or 2 of taking Metformin, contact your physician’s office to see if there is a better option to consider.
It’s also worth considering that in time, as you get you maintain better blood glucose control through diet and lifestyle, you may be able to reduce or stop taking Metformin altogether.
Another thing to note is that Metformin can cause B12 deficiency over time. If you’ve been taking Metformin for several years, it is advisable to get a B12 blood test. This deficiency can easily be corrected through supplementation.
Metformin’s Effectiveness
Metformin is generally not as effective at lower doses, but starting out with smaller doses (ie. 500 mg/day) and titrating slowly to 1,000 mg twice daily (maintenance) will help avert GI side effects.
It’s also recommended never to exceed 2,500 mg/day (maximum dose).
The effectiveness of Metfomin varies from person to person–with some, the initial dose is sufficient, in others, effect is not seen until the max dose is reached, and still in others it is minimally effective.
For many people, healthy diet and lifestyle are sufficient in controlling blood glucose and in others whose biology or hormonal signalling is altered as described above, medication may be required to achieve control – it’s always an individual thing.
Regardless of whether medication is a part of your healthcare plan, it’s always important to make healthy dietary choices including the restriction of carbohydrates, most especially those in the form of white starches (bread, pasta, potatoes, rice) and simple sugars.
Metformin Perks
In comparison with other diabetes medications, Metformin:
- Is weight neutral (and in some may result in slight loss)
- Does not cause hypoglycaemia
- Has a significant glucose lowering effect (preventing onset of diabetes in up to 33% of people enrolled in CDCs DPP)
- No effect on bone loss (as with TZDs and possibly SGLT-2s)
- Protective against cardiovascular disease, cancer, stroke and dementia
- Is non injectable
- Is very cost effective
- Originated from a natural herb and traces its medicinal history back thousands of years
Who should NOT take Metformin
There are a few people for whom Metformin is contraindicated:
- If you are having an X-Ray or CT scan requiring dyes, you will have to temporarily stop taking Metformin
- Because Metformin is cleared by the kidneys, it is contraindicated in kidney disease
- Because Metformin works in the liver, it is contraindicated in liver disease
- In rare cases, Metformin can cause a life threatening condition called lactic acidosis (tell your doctor if you have liver, heart or kidney disease, or drink alcohol)
As with all medications, whether to take Metformin should be a shared decision between you and your physician.
Remember to discuss your goals, current blood sugar control (including HbA1c), family history, length of time you have been diagnosed, and any symptoms you may have.
Keeping a diary/log of medications and symptoms along with a food and glucose journal is very helpful in troubleshooting and making informed decisions regarding your health care in the future.
Please share this info to help others.