{"id":635074,"date":"2026-01-21T10:06:17","date_gmt":"2026-01-21T15:06:17","guid":{"rendered":"https:\/\/www.singlecare.com\/blog\/?p=635074"},"modified":"2026-02-17T11:14:30","modified_gmt":"2026-02-17T16:14:30","slug":"metformin-side-effects-long-term","status":"publish","type":"post","link":"https:\/\/www.singlecare.com\/blog\/metformin-side-effects-long-term\/","title":{"rendered":"Long-term side effects of metformin"},"content":{"rendered":"<p><a href=\"https:\/\/www.singlecare.com\/prescription\/metformin-hcl\"><span style=\"font-weight: 400;\">Metformin<\/span><\/a><span style=\"font-weight: 400;\"> and <\/span><a href=\"https:\/\/www.singlecare.com\/prescription\/metformin-hcl-er-mod\"><span style=\"font-weight: 400;\">metformin extended-release <\/span><\/a><span style=\"font-weight: 400;\">(ER) are oral medications approved to lower blood sugar in people with Type 2 diabetes and prediabetes. Some healthcare providers also prescribe metformin <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/off-label-prescription-drugs\/\"><span style=\"font-weight: 400;\">off-label<\/span><\/a><span style=\"font-weight: 400;\"> for <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/gestational-diabetes-diet-treatments\/\"><span style=\"font-weight: 400;\">gestational diabetes<\/span><\/a><span style=\"font-weight: 400;\">, polycystic ovary syndrome (<\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-dosage-for-pcos\/\"><span style=\"font-weight: 400;\">PCOS<\/span><\/a><span style=\"font-weight: 400;\">), and <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-weight-loss\/\"><span style=\"font-weight: 400;\">weight loss<\/span><\/a><span style=\"font-weight: 400;\">. Metformin is considered a safe and affordable first-line treatment in Type 2 diabetes care. That said, metformin can cause both short-term and long-term side effects.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Here\u2019s what to expect and how to reduce the risk of long-term metformin side effects.<\/span><\/p>\n<h2 id=\"most-common-side-effects-of-metformin\"><span style=\"font-weight: 400;\">Most common side effects of metformin<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">According to clinical trial data, the most common side effect of metformin is diarrhea, which occurred in more than half of participants. Other <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-side-effects\/\"><span style=\"font-weight: 400;\">common side effects of metformin<\/span><\/a><span style=\"font-weight: 400;\"> include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Nausea<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Vomiting<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Flatulence<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Indigestion<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Decreased energy<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Headache<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Other possible <\/span><a href=\"https:\/\/medlineplus.gov\/druginfo\/meds\/a696005.html\"><span style=\"font-weight: 400;\">metformin side effects<\/span><\/a><span style=\"font-weight: 400;\"> include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Change in taste<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Skin flushing<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Muscle aches<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Rash<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Some metformin side effects fade as your body adjusts to the medication. It\u2019s important to stay in contact with a healthcare provider if any side effects become severe or debilitating. For instance, metformin\u2019s gastrointestinal side effects range from mild to severe, according to <\/span><a href=\"https:\/\/grainfoodsfoundation.org\/experts\/angela-ginn-meadow-rd-ldn-cde\/\"><span style=\"font-weight: 400;\">Angela Ginn-Meadow<\/span><\/a><span style=\"font-weight: 400;\">, RN<\/span><span style=\"font-weight: 400;\">, registered dietitian, and certified diabetes educator, based in Baltimore, Maryland. Tell your prescriber if you experience severe <\/span><a href=\"https:\/\/www.singlecare.com\/conditions\/diarrhea-treatment-and-medications\"><span style=\"font-weight: 400;\">diarrhea<\/span><\/a> <span style=\"font-weight: 400;\">or vomiting, as these can quickly lead to <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/dehydration-medication\/\"><span style=\"font-weight: 400;\">dehydration<\/span><\/a><span style=\"font-weight: 400;\">.\u00a0<\/span><\/p>\n\t\t<div id=\"coupon-cta\" class=\"coupon-cta master-template\">\n\t\t\t<p id=\"headline\">Save up to 80% on Metformin with SingleCare<\/p>\n\t\t\t<p id=\"subheadline\">Different pharmacies offer different prices for the same medication. SingleCare helps find the best price for you.<\/p>\n\t\t\t<div class=\"details-wrap\">\n\t\t\t\t<div class=\"details\">\n\t\t\t\t\tMetformin 500 mg (60 Tablets)\t\t\t\t<\/div>\n\t\t\t\t<div class=\"address\">\n\t\t\t\t\t23666 - Hampton, VA\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t<div class=\"api-response\">\n\t\t\t\t\t\t<div class=\"coupon\">\n\t\t\t<div class=\"logo\">\n\t\t\t<img decoding=\"async\" src=\"https:\/\/images.singlecare.com\/content\/images\/pharmacy\/logo-color-kroger.svg\" alt=\"Kroger Pharmacy\" \/>\t\t\t<\/div>\n\t\t\t<div class=\"price\">\n\t\t\t\t<div class=\"price-number\">\n\t\t\t\t\t$5.32<br\/>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"price-signup\">\n\t\t\t\t\t<span class=\"info-icon\">i<\/span>\n\t\t\t\t\tPrice with <a href=\"https:\/\/www.singlecare.com\/prescription\/metformin#blog-cta\">signup<\/a>\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t<div class=\"couponbtn\">\n\t\t\t\t<a target=\"_blank\" href=\"https:\/\/www.singlecare.com\/prescription\/metformin#blog-cta\">Get free coupon<\/a>\n\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"coupon\">\n\t\t\t<div class=\"logo\">\n\t\t\t<img decoding=\"async\" src=\"https:\/\/images.singlecare.com\/content\/images\/pharmacy\/logo-color-harristeeter.svg\" alt=\"Harris Teeter Pharmacy\" \/>\t\t\t<\/div>\n\t\t\t<div class=\"price\">\n\t\t\t\t<div class=\"price-number\">\n\t\t\t\t\t$5.32<br\/>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"price-signup\">\n\t\t\t\t\t<span class=\"info-icon\">i<\/span>\n\t\t\t\t\tPrice with <a href=\"https:\/\/www.singlecare.com\/prescription\/metformin#blog-cta\">signup<\/a>\t\t\t\t<\/div>\n\t\t\t<\/div>\n\t\t\t<div class=\"couponbtn\">\n\t\t\t\t<a target=\"_blank\" href=\"https:\/\/www.singlecare.com\/prescription\/metformin#blog-cta\">Get free coupon<\/a>\n\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t<a target=\"_blank\" href=\"https:\/\/www.singlecare.com\/prescription\/metformin#blog-cta\" class=\"coupon-see-all-btn\">See Metformin prices at all pharmacies<\/a>\n\t\t<\/div>\n\n\t\t\n<h2 id=\"what-are-the-long-term-side-effects-of-metformin\"><span style=\"font-weight: 400;\">What are the long-term side effects of metformin?<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">\u201cLong-term side effects of metformin include <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-and-vitamin-b12\/\"><span style=\"font-weight: 400;\">B12 deficiency<\/span><\/a><span style=\"font-weight: 400;\"> and lactic acidosis,\u201d Ginn-Meadow says. Your healthcare provider should regularly screen for these side effects with blood tests.<\/span><\/p>\n<p><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC10688235\/\"><span style=\"font-weight: 400;\">Up to 30% of long-term metformin users<\/span><\/a><span style=\"font-weight: 400;\"> develop low vitamin B12, which can cause chronic fatigue, memory impairment, and nerve damage. \u201cThis effect worsens with increasing doses of metformin and accumulates over time,\u201d says <\/span><a href=\"https:\/\/www.providence.org\/doctors\/family-medicine\/ca\/santa-monica\/david-cutler-1255368338\"><span style=\"font-weight: 400;\">David Cutler<\/span><\/a><span style=\"font-weight: 400;\">, MD<\/span><span style=\"font-weight: 400;\">, a family medicine physician at Providence Saint John\u2019s Health Center in Santa Monica, California. He says additional risk factors for B12 deficiency include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Older age<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Eating a vegetarian or vegan diet<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Having atrophic gastritis<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Taking<\/span><a href=\"https:\/\/www.singlecare.com\/drug-classes\/proton-pump-inhibitors\"> <span style=\"font-weight: 400;\">proton pump inhibitors<\/span><\/a><span style=\"font-weight: 400;\"> (PPIs)\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Having had stomach or small bowel surgery<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">In very rare cases, this diabetes medicine can cause metformin-associated <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-side-effects\/\"><span style=\"font-weight: 400;\">lactic acidosis<\/span><\/a><span style=\"font-weight: 400;\">, a life-threatening condition in which lactic acid builds up in the body. This is more likely in people with liver problems, kidney problems, or alcohol abuse disorder.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Weight loss can also occur with long-term metformin use. Sometimes it is even prescribed off-label for this purpose.<\/span><\/p>\n<h2 id=\"serious-side-effects-of-metformin\"><span style=\"font-weight: 400;\">Serious side effects of metformin<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Potentially serious side effects of metformin include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><a href=\"https:\/\/www.singlecare.com\/conditions\/low-blood-sugar-symptoms\"><span style=\"font-weight: 400;\">Hypoglycemia<\/span><\/a><span style=\"font-weight: 400;\"> (low blood sugar) when combined with other diabetes medications<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Lactic acidosis<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Allergic reaction<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Complications from metformin-induced B12 deficiency<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">The most serious <\/span><a href=\"https:\/\/www.accessdata.fda.gov\/spl\/data\/8b4401f6-af1d-47ce-b577-c431c3313afe\/8b4401f6-af1d-47ce-b577-c431c3313afe.xml\"><span style=\"font-weight: 400;\">potential side effect of metformin<\/span><\/a><span style=\"font-weight: 400;\"> is lactic acidosis. It requires emergency medical attention, as about 25% of cases are fatal. The good news is that the low risk of lactic acidosis can be significantly decreased with regular kidney health monitoring.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Risk factors of lactic acidosis with metformin include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><a href=\"https:\/\/www.singlecare.com\/blog\/chronic-kidney-disease\/\"><span style=\"font-weight: 400;\">Kidney disease<\/span><\/a><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><a href=\"https:\/\/www.singlecare.com\/blog\/fatty-liver-diet\/\"><span style=\"font-weight: 400;\">Liver disease<\/span><\/a><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Excessive consumption of alcohol<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Taking metformin right before a surgical procedure or CT scan<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Overdosage of metformin<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Signs of lactic acidosis include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Lightheadedness<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Feeling extremely weak or tired<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Unexplained muscle pains<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Trouble breathing<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Severe stomach pain<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Like all medications, metformin can cause allergic reactions. Signs of an allergic reaction include:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Swelling of the face, throat, or hands<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Shallow breathing<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Sudden skin rash<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Finally, <\/span><a href=\"https:\/\/www.singlecare.com\/prescription\/vitamin-b12\"><span style=\"font-weight: 400;\">vitamin B12 deficiency<\/span><\/a><span style=\"font-weight: 400;\"> from long-term metformin use can eventually cause significant health issues such as <\/span><a href=\"https:\/\/www.singlecare.com\/conditions\/neuropathy-treatment-and-medications\"><span style=\"font-weight: 400;\">neuropathy<\/span><\/a><span style=\"font-weight: 400;\">, megaloblastic anemia, and <\/span><a href=\"https:\/\/www.singlecare.com\/conditions\/dementia-symptoms\"><span style=\"font-weight: 400;\">cognitive decline<\/span><\/a><span style=\"font-weight: 400;\">, according to Dr. Cutler. These complications are not direct side effects of the medication, but they are serious health problems to be aware of. People on metformin should have regular blood tests to assess vitamin B12 levels.<\/span><\/p>\n<h2 id=\"metformin-side-effects-in-women-long-term\"><span style=\"font-weight: 400;\">Metformin side effects in women long-term<\/span><\/h2>\n<p><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC8952223\/#sec3-medicina-58-00430\"><span style=\"font-weight: 400;\">Research<\/span><\/a><span style=\"font-weight: 400;\"> on sex-dependent side effects of metformin has found that there is little difference in metformin side effects in female versus male patients over the long term. In general, metformin side effects specific to women are either PCOS-related improvements or a short-term difference in side effect frequency.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">By improving <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/insulin-resistance\/\"><span style=\"font-weight: 400;\">insulin resistance<\/span><\/a><span style=\"font-weight: 400;\">, metformin also helps improve PCOS symptoms in some women. Specifically, metformin can help <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-to-regulate-periods\/\"><span style=\"font-weight: 400;\">regulate periods<\/span><\/a><span style=\"font-weight: 400;\"> and <\/span><a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC6464837\/\"><span style=\"font-weight: 400;\">improve fertility<\/span><\/a><span style=\"font-weight: 400;\">. Fortunately, these metformin effects are typically seen as benefits rather than adverse reactions.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Women may also experience more gastrointestinal side effects of metformin than men at the beginning of treatment. In <\/span><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s40264-020-00913-8#Abs1\"><span style=\"font-weight: 400;\">one study<\/span><\/a><span style=\"font-weight: 400;\">, 34% of women versus 25% of men reported side effects such as diarrhea, nausea, abdominal discomfort, flatulence, headache, or fatigue in the first two weeks of metformin use. However, these side effects improved, and the frequency of side effects in women versus men equalized within a few months of starting treatment. Switching to an extended-release version of metformin (metformin XR) can help decrease its GI side effects.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\t\t<div class=\"singlecare-dynamic-newsletter-wrapper sin-newsletter-wrapper\">\n\t\t\t<span class=\"heading\">Get our diabetes newsletter<\/span>\n\t\t\t<form class=\"form-wrapper\" data-newsletter-form=\"1\" data-subsource=\"Diabetes Newsletter\">\n\t\t\t\t<div class=\"input-wrapper\">\n\t\t\t\t\t<label for=\"dynamic-email\">Email<\/label>\n\t\t\t\t\t<input type=\"email\" id=\"dynamic-email\" class=\"email\" required>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"input-wrapper\">\n\t\t\t\t\t<input class=\"submit-form-btn\" type=\"submit\" value=\"Click to sign up\">\n\t\t\t\t<\/div>\n\t\t\t<\/form>\n\t\t\t<p class=\"success-message\" aria-live=\"polite\"><\/p>\n\t\t<\/div>\n\t<\/span><\/p>\n<h2 id=\"metformin-side-effects-in-men-long-term\"><span style=\"font-weight: 400;\">Metformin side effects in men long-term<\/span><\/h2>\n<p><a href=\"https:\/\/ec.bioscientifica.com\/view\/journals\/ec\/8\/10\/EC-19-0382.xml\"><span style=\"font-weight: 400;\">One small study<\/span><\/a><span style=\"font-weight: 400;\"> found that men may be more likely than women to experience metformin-induced vitamin B12 deficiency. Regular screening for nutritional deficiencies can prevent this from becoming a long-term problem.\u00a0<\/span><\/p>\n<h2 id=\"considerations-when-taking-metformin-long-term\"><span style=\"font-weight: 400;\">Considerations when taking metformin long-term<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Metformin is typically a long-term medication. Some people take it daily for the rest of their lives to manage blood sugar levels. Long-term use is considered safe as long as the patient commits to the following:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Regularly monitoring blood glucose levels<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Scheduling routine check-ups<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Reporting new or worsening side effects to their prescriber<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Consulting their prescriber before starting any new medications (including over-the-counter drugs and supplements)<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Not discontinuing metformin without guidance from a healthcare provider<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">\u201cPatients taking metformin long-term should have B12 levels checked every two to three years,\u201d Dr. Cutler says. \u201cTesting should be done sooner if neuropathy develops, unexplained anemia develops, or if a patient has additional risk factors.\u201d<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Metformin can <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/metformin-interactions\/\"><span style=\"font-weight: 400;\">interact with other diabetes or blood sugar-related medications<\/span><\/a><span style=\"font-weight: 400;\">. To avoid drug interactions, your healthcare provider needs to have a complete list of any prescription drugs, supplements, and over-the-counter medications you currently take.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Finally, never <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/stopping-metformin\/\"><span style=\"font-weight: 400;\">stop taking metformin<\/span><\/a><span style=\"font-weight: 400;\"> without a healthcare professional&#8217;s guidance. While metformin is not known to cause withdrawal symptoms, quitting this medication can cause high blood sugar and increased A1C. In the short term, <\/span><a href=\"https:\/\/www.singlecare.com\/conditions\/high-blood-sugar-symptoms\"><span style=\"font-weight: 400;\">high blood sugar<\/span><\/a><span style=\"font-weight: 400;\"> can cause extreme hunger or thirst, frequent urination, blurry vision, and mood changes. Over time, elevated A1C can cause <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/diabetes-complications\/\"><span style=\"font-weight: 400;\">diabetes complications<\/span><\/a><span style=\"font-weight: 400;\"> such as vision problems, foot problems, increased risk for heart attack and stroke, and irreversible nerve damage.\u00a0<\/span><\/p>\n<h2 id=\"how-to-manage-long-term-metformin-side-effects\"><span style=\"font-weight: 400;\">How to manage long-term metformin side effects<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">The good news is that there are ways to prevent long-term metformin side effects, including vitamin B12 deficiency, lactic acidosis, and hypoglycemia:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Vitamin B12 deficiency: <\/b><span style=\"font-weight: 400;\">Vitamin B12 deficiency can be detected early through routine screening. And the good news is that supplementation typically resolves the issue, according to Dr. Cutler.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Lactic acidosis: <\/b><span style=\"font-weight: 400;\">This is a very rare metformin side effect that can be prevented if you keep appointments for liver and kidney function screenings, drink alcohol in moderation, and follow any pre-operative and<\/span><a href=\"https:\/\/www.mayoclinic.org\/drugs-supplements\/iodixanol-injection-route\/precautions\/drg-20150989\"> <span style=\"font-weight: 400;\">pre-CT scan<\/span><\/a><span style=\"font-weight: 400;\"> instructions for metformin dosage. Metformin is often temporarily withheld for two to three days prior to a surgical procedure.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Hypoglycemia: <\/b><span style=\"font-weight: 400;\">Low blood sugar is not a long-term side effect of metformin, but it can develop in combination with other diabetes medications. That\u2019s because lifestyle changes like diet and exercise can improve blood sugar control to the point that metformin dosage should be lowered.\u00a0<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">The most important thing to remember about managing metformin side effects is to stay connected with a healthcare team. Report new or worsening side effects. Seek personalized medical advice before starting any new drugs or supplements. When in doubt, consult your prescriber. If you are concerned about metformin side effects or want to switch <\/span><a href=\"https:\/\/www.singlecare.com\/blog\/best-diabetes-drug-for-weight-loss\/\"><span style=\"font-weight: 400;\">diabetes medications<\/span><\/a><span style=\"font-weight: 400;\"> for any reason, make an appointment to see a healthcare professional.<\/span><\/p>\n<h2 id=\"bottom-line-is-it-safe-to-take-metformin-long-term\"><span style=\"font-weight: 400;\">Bottom line: Is it safe to take metformin long-term?<\/span><\/h2>\n<p><span style=\"font-weight: 400;\">Metformin is often prescribed for long-term use. It is typically well-tolerated, and initial side effects tend to improve within weeks of starting the medication. Serious side effects are rare, but it\u2019s important to know the signs. Contact a healthcare provider immediately if you experience signs of lactic acidosis (e.g., extreme fatigue, trouble breathing, or stomach pain), allergic reactions (e.g., facial swelling, shortness of breath, or rapid heartbeat), or dangerously low blood sugar (e.g., dizziness, confusion, or loss of consciousness).<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Metformin and metformin extended-release (ER) are oral medications approved to lower blood sugar in people with Type 2 diabetes and prediabetes. Some healthcare providers also prescribe metformin off-label for gestational diabetes, polycystic ovary syndrome (PCOS), and weight loss. Metformin is considered a safe and affordable first-line treatment in Type 2 diabetes care. That said, metformin [&hellip;]<\/p>\n","protected":false},"author":149,"featured_media":635076,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[4589],"tags":[10298,12752],"coauthors":[20942],"class_list":["post-635074","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-drug-info","tag-diabetes","tag-medication-side-effects","wpautop"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.4 (Yoast SEO v27.4) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>Are there long-term side effects of metformin?<\/title>\n<meta name=\"description\" content=\"Long-term side effects of metformin may include B12 deficiency and lactic acidosis. 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