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    Metformin Side Effects

    Metformin medication can be used for several things but is most often prescribed as a treatment for the symptoms of diabetes. It helps to lower blood sugar levels and improve cholesterol.

    As with anything, there are sometimes side effects to the medication, making it necessary to learn about the risks and become knowledgeable on how the drug is used before making the decision to start it.

    Quick Overview

    Used to treat symptoms of Type 2 Diabetes, metformin controls the amount of glucose that gets into the blood. Your liver will release less sugar into the bloodstream with the help of this medication.

    Your body will also no longer absorb as much glucose from the foods you eat. This greatly helps to control symptoms of your diabetes.

    The medication cannot be used for people with Type 1 Diabetes, as this condition prevents the body from producing insulin. It will not be able to control the sugar levels in the bloodstream as intended.

    Glucophage is the name this antidiabetic medication is trademarked under. The tablets appear white or off-white and contain the inactive ingredients magnesium stearate and povidone.

    Metformin hydrochloride is the active ingredient. These pills come in either 500 milligrams, 850 milligrams, or 1,000 milligrams.

    The coating is different for the 1,000-milligram option. It uses polyethylene glycol and hydroxypropyl methylcellulose. The two smaller doses do not include the polyethylene glycol.

    How Does Metformin Work?

    Metformin works to increase your body’s own response to insulin. This substance should be found naturally in the body, but others may require an insulin shot to get it.

    It is often advised to try metformin first to see if the medication will be enough to control blood sugar and keep glucose levels from reaching a high point.

    Known as a biguanide, this antidiabetic medication is one of the first recommendations for controlling symptoms of Type 2 diabetes. It will ensure muscle cells are sensitive to insulin so they can eliminate sugar from the bloodstream in a timely manner.

    You should not experience a spike in blood sugar after consuming a meal if you’re taking metformin.

    There are additional brand name options for metformin. Glucophage is the most common,  others include Fortamet, Glumetza, and Riomet which may be in a different form or be released in a different place in the body. Discuss the different options with your doctor.

    What are Some Common Metformin Side Effects?

    Metformin medication may cause a few minor side effects. You may experience a mild headache.

    Diarrhea is also common as your body adjusts to the pills. If you notice a metallic taste in your mouth, nausea, gas, upset stomach, or heartburn.

    While these generally go away after a few days and are not typically considered serious, you should contact your healthcare provider if you have any concerns at all.

    Rare Metformin Side Effects

    A rare, but a possibly severe side effect of metformin use is lactic acidosis. This disease is life-threatening. You could go into shock or experience organ failure, resulting in death.

    Lactate builds up in the body and your bloodstream will have an incredibly low pH level. If you notice a severe decrease in your appetite, have overall body discomfort or weakness, and any headaches or muscle cramps that do not go away, seek medical attention immediately.

    Are the Side Effects Immediate?

    Some side effects are immediate and will be noticed after the first dose or two. Others may take several days or even weeks to kick in.

    It depends on how your body handles the medication, what your diet is like, and whether you have any other prescriptions that are interacting at the time. Any time a side effect is noticed that you’re worried about, you can discuss it with your doctor to get their opinion on whether it’s normal or not.

    More Serious Metformin Side Effects

    Some of the more serious side effects caused by metformin can include an allergic reaction that looks like a rash or hives. You may also experience itching and have swelling in the face or in the tongue or lips.

    An allergic reaction like this requires immediate medical attention and your doctor may need to find you a new medication if this occurs.

    You could potentially experience breathing problems and feeling faint or lightheaded as well. If you experience symptoms of very low blood sugar, such as sweating, feeling cold, dizzy, weak, or especially hungry, then contact your doctor to see what to do.

    The 1000mg metformin side effects are sometimes severe like this while the metformin 500mg side effects are less serious.

    Other serious side effects include:

    • Muscle aches
    • A slow heartbeat
    • Severe stomach pain
    • Feeling incredibly weak and tired

    Chest pains are another serious side effect that needs to be addressed immediately. This could be an indicator of heart attack or stress to your heart.

    Are There Long Term Side Effects or Harm Caused By Metformin Use?

    Long term, metformin has the potential to cause damage to the kidneys and liver. People who currently have poor kidney or liver function should not begin taking the medication.

    If symptoms of damage or failure develop, the use of metformin should be discontinued. Those with a healthy kidney and healthy liver who experience no unusual symptoms should be fine to continue the medication as their doctor prescribes.

    Metformin’s Drug Identification Number

    Every drug receives its own identification number. Metformin hydrochloride comes in many forms, some of which have been discontinued.

    The list of NDA identification numbers is quite extensive, depending on the company that’s offering them, the dosage, and whether they’re in regular tablet or the extended release version. The main trademarked name, Glucophage, is 020357.

    Metformin Dosage

    The dosage you take will depend on the severity of your symptoms, your weight, and reasons for needing to take the medication, such as for PCOS (Polycystic Ovary Syndrome). You could be prescribed a 500, 850, or 1,000 mg dose.

    You will take the medication by mouth either in tablet form or an extended-release tablet. There is also a liquid version sometimes prescribed to those who have a hard time taking pills.

    The metformin 500 mg side effects may be less significant than 1000 mg metformin side effects. Be sure to discuss any problems with your doctor so he or she may decide what dose would be best for you.

    A higher dose that only causes minor discomfort may be recommended still to ensure your blood glucose levels can drop efficiently.

    The time you take your dose will also vary, but it is recommended to take it at the same time every day to make it easier to remember. Many people take their medication with a meal two times a day.

    It could be once a day for the liquid version and up to three times per day for a tablet. Read your medication label carefully and discuss it with your doctor to ensure you’re taking the right dosage.

    Your doctor may start you out on a smaller dose first for a week or two before trying you on a higher amount to see how your body handles it.

    The metformin treatment success rate is on the higher end for diabetes medications because doctors are very familiar with it. They know which doses to start with and how much to up the amount to in those patients who need extra assistance.

    Other medications are not as commonly well-known, even by doctors. They are less likely to prescribe them until after metformin has found to be ineffective.

    How Much Metformin Should You Try Before Moving On?

    You should follow your doctor’s instructions when taking metformin. The amount of time to try may vary for each person.

    Because the metformin treatment cost is so affordable, many people continue to take it past the time they should. Some people opt to stop because they have some gastrointestinal trouble, such as diarrhea, gas, or an upset stomach.

    Discuss these with your healthcare provider, he or she may decide that the positive effects of metformin outweighs these side effects that typically fade over time.

    It may be recommended by your doctor to try the extended release option if getting a full dose at once is causing your discomfort. This should be tried before stopping altogether.

    Symptoms often subside once your body becomes accustomed to the dose.

    The American Diabetes Association even recommends taking this medication or another like it to help control symptoms. Diet and exercise alone may not be enough.

    Your target blood glucose levels need to stay in check if you want to remain as healthy as possible with this disease. The metformin treatment success rate is one of the highest for diabetes medications.

    If you do need to stop taking metformin, stopping cold-turkey. Instead, your doctor might want you to gradually decrease your dosage until your body gets used to functioning on its own without it.

    Going off of certain medications immediately can cause adverse reactions.

    Many people take metformin for years with no side effects. The medication continues to remain effective.

    If you do not see results within four or five days of use, doctors may suggest taking a compound medication instead that combines metformin with another option. If this still does not work, you may require insulin shots as well.

    When to Consult or Contact Your Doctor?

    Consult your doctor if you feel metformin might be right for you. The medication can be used to treat several issues and not just diabetes.

    Metformin for PCOS is one option. Polycystic Ovary Syndrome affects hormone levels and can make it difficult for women to conceive.

    The extra hormones cause many to miss a menstrual cycle. Some never even have a cycle at all. Using metformin for PCOS can help women to have normal menstrual cycles so they may try to get pregnant naturally.

    Metformin for weight loss is also possible. Ask your doctor about using this medication to shed some weight.

    The metformin treatment may suppress your appetite so you are not feeling as hungry as usual. Using metformin for weight loss is not always recommended, so speaking with your doctor extensively will help you make the right decision.

    If you’re currently taking metformin and experience serious side effects, it is also advisable to talk to your doctor. You may need to try a different dosage or perhaps try another medication altogether. Metformin will not work for everyone.

    When having surgery, your surgeon should be notified of your metformin prescription. He or she may require you to stop taking it for a period of time before the procedure occurs, and wait for at least 48 hours afterward to start using it again. This will ensure there is no interference.

    Risks of Metformin

    There are some small risks when taking metformin, as well as a few major risks. Small risks include the chance of developing stomach discomfort, diarrhea, nausea, and headaches.

    These risks are minor and should only be experienced for a short duration, if at all.

    Another possible risk is the development of a B12 deficiency. This is a possibility with Glucophage in particular but can occur with any metformin prescriptions.

    It is important to monitor hematological parameters every year and levels of the B12 vitamin every two or three years of use. Any abnormalities should be closely monitored.

    Major risks include developing kidney, lung, or heart problems. This is very rare but still possible. Just be sure to watch out for symptoms so you can seek medical help immediately if you notice something is off.

    Lactic acidosis is one of the most severe results of long term metformin use that should not be dismissed.

    Do Not Take metformin If:

    You should not take metformin if you have significantly reduced functioning in your kidneys. The FDA formerly advised that the medication should not be used for anyone with even slightly reduced kidney function, but has since revised their warning.

    In 2016, it was revised that only major cases should be excluded.

    If you suffer from moderate kidney issues, metformin should still be safe to take by following your doctor’s instructions. Doctors once looked at only blood creatinine levels to determine who could take the medication without further damage to the kidneys.

    Now, it is required that a glomerular filtration rate estimating equation be used to provide more accurate results. Patients with results on this test that range between 30-45 mL/minute/1.73 m2 should not take this medication.

    You should not take metformin if you are allergic to the medication or any of its ingredients. If there are similar medications you are allergic to, you should consult with your doctor about whether or not this option is a safe one for you.

    If you are a heavy drinker metformin may be contraindicated. Alcohol can have significant interference with the medication and cause your blood sugar levels to drop or rise to dangerous levels. It also has the potential to cause lactic acidosis, which can be fatal.

    People over the age of 80 may be advised against taking metformin. People of younger ages may also be warned against it if they have other issues, such as non-working kidneys.

    People of any age who have had a stroke, heart attack, or severe infection also have increased the risk for developing the same or worse conditions if they take this medication.

    Metformin Interactions

    Lactic acidosis, a serious side effect of metformin, has increased risk when taking certain other medications. If you have any concerns about drug interactions consult your pharmacist or doctor.

    You should also let your doctor know if you take a form of acetazolamide, commonly called Diamox. This diuretic that can also assist with certain eye problems may not mix well with metformin.

    Both dichlorphenamide and methazolamide prescriptions should also be brought to your doctor’s attention before starting metformin. Dichlorphenamide is often prescribed to people who suffer from primary periodic paralysis.

    It decreases the attacks that cause muscle weakness. Methazolamide is commonly used for treating eye pressure due to glaucoma.

    It is also not advised to drink alcohol when taking metformin or many of the other diabetes medications. It can increase your risk of developing lactic acidosis.

    You may also experience extremely high levels of blood sugar. Long-term alcohol use can cause hyperglycemia.

    With this, damage can be caused to your nerves, organs, and vessels. You may experience dehydration, blurred vision, headaches, or fatigue.

    Speak with your doctor about other medications you may be prescribed. Some may not interfere if the doses are changed. Others will interfere no matter what dosage you use.

    What Other Diabetes Drugs and Treatments are There?

    Many other diabetes drugs and treatments are available. The American Diabetes Association lists the available options, though each one will not be right for every person.

    It is best to speak to your doctor and your insurance company about the choices available and see which one is right for you.

    Alpha-glucosidase inhibitors block the body from breaking down starches and slow down the breakdown of certain sugars. Medications such as acarbose and miglitol fall under this category. Gas and diarrhea are common side effects.

    Thiazolidinediones such as rosiglitazone and pioglitazone cause insulin to work more efficiently within the fat and muscle of the body. They can also help the liver to stop creating glucose.

    These medications require you to be carefully monitored as they may cause liver troubles and also have a higher chance of developing heart disease than many of the other options.

    Sodium-glucose transporter 2 reabsorbs glucose in the kidneys. SGLT2 inhibitors prevent this from happening.

    The extra glucose that would have been absorbed by the body and caused levels to skyrocket to dangerous levels will instead be flushed out during urination.

    Yeast infections and urinary tract infections are more common because of this, so people with a history of having them should avoid taking this type of medication.

    Three main types are put into this category, including empagliflozin, dapagliflozin, and canagliflozin.

    Bile acid sequestrants, such as colesevelam, lower cholesterol. It can reduce bad cholesterol levels while simultaneously reducing levels of glucose.

    This option may be valid for those who already experience liver problems and want to decrease the effects medications could cause on this vital organ.

    Helping the pancreas to release insulin, sulfonylureas like chlorpropamide, glyburide, glimepiride, and glipizide are other options for people with diabetes. These medications vary a great deal in side effects so many doctors do not prescribe them as easily.  

    Meglitinides help beta cells release insulin. You take them before your three main meals each day.

    You may experience extremely low blood glucose levels with this mediation because your body is releasing much more insulin. The two main options are repaglinide and nateglinide.

    Dopamine-2 Agonists, such as bromocriptine, can lower levels of blood glucose after you’ve eaten. DPP-4 inhibitors, such as sitagliptin, saxagliptin, linagliptin, and alogliptin, prevent certain compounds from breaking down.

    These compounds help to reduce levels of blood sugar quickly. They do not cause weight gain as some other medications do.

    Combination medications are also available. Some combine two active ingredients to lower blood glucose while also providing another function, such as increasing insulin production.

    Metformin is paired with several other options for double combinations. Actoplus Met, Avandamet, Invokamet, Janumet, Jentadueto, Kazano, Kombiglyze, Prandimet, Segluromet, Synjardy, and Xigduo are some of the names you may see with combination medications for diabetes patients.

    Whether you’re using metformin for diabetes treatment as intended, got prescribed the medication for help with Polycystic Ovary Syndrome, or are trying to lose weight, it is best to know all of the risk factors.

    Speak with your doctor about your reason for wanting to try the metformin treatment and see if he or she agrees it would work for you.