Table of ContentsView AllTable of ContentsHow Metformin WorksOptionsTestingLifestyle ChangesAlternative MedicationsFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
How Metformin Works
Options
Testing
Lifestyle Changes
Alternative Medications
Frequently Asked Questions
Along with lifestyle changes,metformincan help you get yourblood sugar, also called blood glucose, under control. If your blood sugar is not controlled, metformin may not be working for you, and you may need to replace it.
Here’s what to expect when metformin needs to be replaced.
Grace Cary / Getty Images
Metformin is an oral medication used to treattype 2 diabetes. It belongs to a class of drugs calledbiguanides.
Diabetes occurs when your blood sugar reacheshigher than normal levelsdue to an insufficient amount ofinsulinin your body or an improper reaction of your cells to insulin.
Metformin is used to control your blood sugar when diet and exercise changes are not sufficient to manage it. It is often the first medication used when drug therapy is needed to control type 2 diabetes.
The primary mechanisms of metformin lower blood glucose levels in the following ways:
Metformin differs from otherdiabetes medicinesbecause it doesn’t increase insulin production. Diabetes medications that increase insulin production put you at risk of developing drug-inducedhypoglycemia, or low blood sugar. Metformin can also help with weight loss, while most other diabetes medications cause weight gain.
Metformin is prescribed as an immediate-release tablet, oral solution, or extended-release drug. Common brand names for metformin include:
Popularity of Metformin
Discussing Options With Your Healthcare Provider
After your initial diagnosis of type 2 diabetes, your healthcare provider will discuss your treatment options for managing your blood sugar levels and preventing disease complications. They will establish a treatment regimen based on the severity of your condition and many other factors. These considerations include:
Known side effects are a major consideration in choosing a treatment for type 2 diabetes. Taking metformin can increase your risk of developing the following side effects:
Serious Side Effect of MetforminMetformin can occasionally cause lactic acidosis, a serious, life-threatening condition that involves the buildup of lactic acid in your bloodstream. It develops as a result of an imbalance between the use and production of lactic acid. The condition can be fatal if left untreated.Contact your healthcare provider as soon as possible if you experience any of the following symptoms while taking metformin.Symptoms of lactic acidosis include:Persistent vomiting, nausea, or abdominal painUnexplained tirednessShortness of breathRapid breathingEnlarged or tender liverCold or blue hands and feetAbnormal heartbeatWeight loss
Serious Side Effect of Metformin
Metformin can occasionally cause lactic acidosis, a serious, life-threatening condition that involves the buildup of lactic acid in your bloodstream. It develops as a result of an imbalance between the use and production of lactic acid. The condition can be fatal if left untreated.Contact your healthcare provider as soon as possible if you experience any of the following symptoms while taking metformin.Symptoms of lactic acidosis include:Persistent vomiting, nausea, or abdominal painUnexplained tirednessShortness of breathRapid breathingEnlarged or tender liverCold or blue hands and feetAbnormal heartbeatWeight loss
Metformin can occasionally cause lactic acidosis, a serious, life-threatening condition that involves the buildup of lactic acid in your bloodstream. It develops as a result of an imbalance between the use and production of lactic acid. The condition can be fatal if left untreated.
Contact your healthcare provider as soon as possible if you experience any of the following symptoms while taking metformin.
Symptoms of lactic acidosis include:
Regular testing can help your healthcare provider monitor your type 2 diabetes and look for signs that metformin is working as expected. While testing may seem inconvenient at times, it can help identify potential complications before they become difficult to treat and create other health conditions.
Blood Sugar
Taking any oral diabetic medication usually includes having the following laboratory tests every three to six months, though the timing between these tests may be shorter or longer based on your condition:
You can also monitor your blood sugar levels at home. If you are controlling your blood sugar with metformin, you may not have to measure your blood sugar levels every day. Your healthcare provider will help you establish a schedule for home testing based on your condition and the types of medication you take.
You’ll require special equipment to measure your blood sugar levels at home. These options include:
Vitamin B12
Studies indicate that vitamin B12 deficiency may be present in up to 30% of diabetes patients who take metformin. There is evidence that vitamin B12 levels decrease as the length of time and dose of metformin increase.
Without treatment, a vitamin B12 deficiency can lead to the following conditions:
Recommendations from the American Diabetes Association and the American Association of Clinical Endocrinologists suggest monitoring vitamin B12 levels in diabetes patients taking metformin. Testing is advised every two to three years for all diabetic patients taking metformin. It is especially important for those who developperipheral neuropathyand/oranemiawhile taking metformin.
A vitamin B12 deficiency can be measured in one of the following blood tests:
If you’re diagnosed with a vitamin B12 deficiency, your healthcare provider will prescribe therapy based on the cause and severity of the problem. Oralvitamin B12 supplementscan increase levels for those with a moderate deficiency. You may need vitamin B12 injections or ablood transfusionto treat a serious vitamin B12 deficiency.
Whether you are taking metformin or another diabetes medication, lifestyle changes are essential for managing blood sugar levels in diabetes. When supported with appropriatediabetes self-management educationfrom a licensed professional, you can optimize your lifestyle choices from diagnosis through the changes that occur with disease progression.
Together, exercise and diet modifications can help you control blood sugar and lower your risk of complications.
Exercise
Working with an exercise professional can help you plan a program to help you achieve these goals safely and consistently. If you are becoming more active after living a sedentary lifestyle, check with your healthcare provider before you begin any exercise program more intense than brisk walking.
Diet
Establishing a diet that supports normal blood glucose levels can help you manage type 2 diabetes. A registered dietitian or diabetes educator can help you make choices that align with your preferences, lifestyle, goals, and health condition. Eating the right foods can help you avoid serious health problems like vision loss and health issues that can occur with uncontrolled diabetes.
You should also limit foods that are high in carbohydrates and sugars, including foods from the following categories:
Type 2 Diabetes Medication and Treatment
When metformin is not enough, you may be advised to add a new medication to your existing regimen. Or, you may be advised to take a different medication in place of metformin. It is not uncommon to take two or three different diabetes medications at the same time. The specific medication you’re prescribed depends on your condition.
Several classes of drugs are used as alternatives to metformin. There is no standard recommended course of treatment. When metformin fails, you may be prescribed one of the following types of medications:
Summary
Metformin is an oral diabetes drug that can help control blood sugar, also called blood glucose. It is viewed as the gold standard for non-insulin treatment of type 2 diabetes.
In some cases, the drug may stop working due to disease progression or changes to diet and workout programs. The effect can result in blood sugar levels that are too high. It is key to correct treatment failure to avoid disease complications.
When metformin is no longer useful, your healthcare provider may choose to replace it or combine it with a new drug. Adding insulin treatment may be a choice.
A Word From Verywell
Metformin is well regarded as a first-level drug for controlling blood sugar levels in type 2 diabetes. To get optimal benefits, take the drug as prescribed and follow up with recommended office visits and tests.
Dealing with diabetes can be overwhelming. Don’t be afraid to reach out for help. Consulting with a registered dietician and personal trainer can help you establish healthy habits to control your disease and avoid serious complications.
Consider joining an online or in-person diabetes support group to help you deal with the practical and emotional aspects of this lifelong disease and the challenges involved in maintaining good health.
Frequently Asked QuestionsMost people can take long-term metformin therapy without the drug losing its effectiveness. When results change with metformin, it is more often due to the changes that occur with the natural progression of diabetes. Other factors, like drug interactions, improper dosage, or changes in lifestyle, can also affect how the drug works.Learn MoreCommon Signs Metformin Is Not Working and What to DoWhile there are several medications that interact with metformin, it is not common. Taking Tagamet (cimetidine), furosemide, or Adalat (nifedipine) with metformin can increase the concentrations of metformin in your body. Rayos (prednisone), estrogen,progesterone,testosterone,contraceptive pills, and otherdiabetes medicinescan also affect the results of metformin. Morphine, Qualaquin (quinine), Lanoxin (digoxin), quinidine, Midamor (amiloride), Dyrenium (triamterene), Vancocin (vancomycin), and Primsol (trimethoprim) may also cause interactions.Metformin may lower blood sugar within one to two weeks of starting to take this drug. However, it may take up to two to three months to see the full impact of this drug on your blood glucose control. Monitoring your blood glucose levels can help you and your healthcare provider track the effectiveness of metformin.Learn MoreWhy It’s Important to Monitor Glucose Levels
Most people can take long-term metformin therapy without the drug losing its effectiveness. When results change with metformin, it is more often due to the changes that occur with the natural progression of diabetes. Other factors, like drug interactions, improper dosage, or changes in lifestyle, can also affect how the drug works.Learn MoreCommon Signs Metformin Is Not Working and What to Do
Most people can take long-term metformin therapy without the drug losing its effectiveness. When results change with metformin, it is more often due to the changes that occur with the natural progression of diabetes. Other factors, like drug interactions, improper dosage, or changes in lifestyle, can also affect how the drug works.
Learn MoreCommon Signs Metformin Is Not Working and What to Do
While there are several medications that interact with metformin, it is not common. Taking Tagamet (cimetidine), furosemide, or Adalat (nifedipine) with metformin can increase the concentrations of metformin in your body. Rayos (prednisone), estrogen,progesterone,testosterone,contraceptive pills, and otherdiabetes medicinescan also affect the results of metformin. Morphine, Qualaquin (quinine), Lanoxin (digoxin), quinidine, Midamor (amiloride), Dyrenium (triamterene), Vancocin (vancomycin), and Primsol (trimethoprim) may also cause interactions.
Metformin may lower blood sugar within one to two weeks of starting to take this drug. However, it may take up to two to three months to see the full impact of this drug on your blood glucose control. Monitoring your blood glucose levels can help you and your healthcare provider track the effectiveness of metformin.Learn MoreWhy It’s Important to Monitor Glucose Levels
Metformin may lower blood sugar within one to two weeks of starting to take this drug. However, it may take up to two to three months to see the full impact of this drug on your blood glucose control. Monitoring your blood glucose levels can help you and your healthcare provider track the effectiveness of metformin.
Learn MoreWhy It’s Important to Monitor Glucose Levels
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