In a large clinical trial, people taking metformin lost at least 5% of their body weight in 1 year. If your initial weight is 250 pounds, that’s a weight loss of 12.5 pounds.
Is a metformin weight loss prescription medically necessary for you? Find an online weight loss specialist on Klarity Health and find out. If they recommend metformin, get a prescription online in as little as 24 hours.*
Providers on Klarity Health are independent practitioners with clinical autonomy; a diagnosis, treatment, or prescription is not guaranteed.
Providers on Klarity Health are independent practitioners with clinical autonomy; a diagnosis, treatment, or prescription is not guaranteed.
Metformin is a medication primarily to treat type 2 diabetes. It’s sold as generic metformin and brand-name medications Glucophage, Glumetza ER (extended-release), and Riomet (a liquid).
Medications with metformin as the active ingredient and generic metformin are U.S. Food and Drug Administration (FDA)-approved as an antidiabetic agent — aka to help people with type 2 diabetes manage their blood sugar levels when combined with diet and exercise. People taking it sometimes also lose weight. And it’s used off-label (for something it’s not FDA-approved for) for weight loss. It’s used off-label for other things and is being studied to treat cancer, aging, and more.
Unlike popular weight loss medication injections, metformin is a pill or liquid taken by mouth. It can also be taken with other type 2 diabetes and weight loss medications, like Ozempic or Zepbound.
Metformin works for type 2 diabetes and may affect weight by increasing insulin sensitivity, decreasing the amount of sugar your liver makes, and changing how much sugar your intestines absorb. The result is lower blood sugar levels after you eat and when you’re not eating. When you’re more sensitive to insulin, you feel hungrier. You also store more — and burn less — fat. When your insulin and blood sugar are at optimal levels, your body burns fat instead of storing it and you feel less hungry.
Metformin may also affect hormones that impact hunger and reduce your appetite. It may even change the composition of your gut microbiome as part of how it works for weight loss.
Note that the FDA hasn’t approved metformin for weight loss because research findings on its effect on weight aren’t consistent. It’s sometimes used off-label for managing gestational diabetes (during pregnancy) weight gain issues caused by antipsychotic medications, preventing type 2 diabetes, and treating and preventing polycystic ovary syndrome (PCOS).
Metformin is FDA-approved for people over 10 who have type 2 diabetes and need help lowering their blood sugar levels. If you take it, you should also exercise and eat a healthy diet.
If your healthcare provider thinks you’ll benefit from metformin for other needs, such as weight loss, they can prescribe it off-label.
Taking metformin starts with getting a prescription. You can get a prescription from a trained, licensed healthcare provider, such as a physician assistant (PA), medical doctor (MD), or nurse practitioner (NP) if they think it’s medically necessary for you.
Find a board-certified, licensed provider to discuss a medical weight loss program that may include medication, such as metformin, on Klarity Health.
If you and your provider decide metformin weight loss is right for you, your provider can send your metformin prescription to any online or local pharmacy or you can take or send it in yourself.
Metformin comes as a pill you take by mouth in both immediate- and extended-release (ER) formulas and as a liquid. Immediate-release tablets come in 500-, 625-, 850-, and 1000-milligram pills. The extended-release tablets come as a 500-, 750-, or 1000-milligram pill. The 500-milligram (5-milliliter) liquid comes in 4-ounce (118 milliliter) and 16-ounce (473-milliliter) bottles.
There’s no specific dose for metformin for weight loss or type 2 diabetes. You’ll most likely start at 500 milligrams twice a day or 850 milligrams once a day with meals. Your provider may have you increase your dose by 500 milligrams every 2 weeks up to a maximum dosage of 2550 milligrams. If you take more than 2000 milligrams, your provider may suggest taking it across 3 doses a day.
Dosing for children starts at 250 milligrams a day and increases 500 milligrams twice a day after a week up to a maximum dose of 850 milligrams twice a day, depending on age.
If you have side effects from metformin, you’ll most likely have diarrhea, nausea, or vomiting. You may also have gas, weakness, indigestion, stomach discomfort, and/or a headache.
More serious side effects are possible, but less common, and can include lactic acidosis (where your blood becomes too acidic), vitamin B–12 deficiency, allergic reactions, and kidney problems.
Be sure to talk to your provider and/or pharmacist about potential side effects and any you have. And, if you start metformin, consider reporting any negative side effects you have to the FDA by visiting MedWatch or calling 1-800-FDA-1088.
Generic metformin tablets are fairly inexpensive. The retail price for 30 immediate-release tablets is about $28 according to drugs.com and with its discount. Extended-release tablets are only slightly more at $18 a month for 30 tablets The generic liquid is $145 for 118 milliliters or $552 for 473 milliliters.
Brand-name versions are more expensive. Glucophage costs up to $70 for 60 immediate-release tablets. 30 tablets of Glumetza ER cost up to $1,588 with the GoodRx discount. Riomet (an oral solution) costs about $184 for 118 milliliters or $709 for 473 milliliters.
Compared to the 5% weight loss people have with metformin, people lose more on other drugs. Up to 10% on Ozempic — another medication for type 2 diabetes that helps people lose weight, up to 13.9% on Mounjaro, and up 20.9% on Zepbound.
So metformin isn’t the most effective weight loss drug overall. But, if you can’t take other weight loss or antidiabetic medications, it’s a solid option. Your insurance company may also want you to take it for blood sugar control before approving another antidiabetic medication due to cost.
Ozempic and Mounjaro are FDA-approved improve glycemic (blood sugar) control for adults with type 2 diabetes. Zepbound is FDA-approved for weight loss or weight management in people with obesity and overweight when combined with a reduced-calorie diet and increased physical activity. Side effects for any of them may include, but aren’t limited to, nausea, vomiting, constipation, diarrhea, and headaches.
Only you and your healthcare provider can decide which medication is right for you and your needs.
Learn more about Metformin vs Ozempic for weight loss.
Testimonials from real patients who received treatment from healthcare providers on Klarity Health.
Providers on Klarity Health are licensed, board-certified, and offer a personalized approach to your unique weight-loss needs. See detailed profiles for each provider and find an approach that’s best for you. (Costs for treatment options may vary.)
Your journey to losing weight starts with an initial consultation. Your provider will go over your goals and medical history to recommend a weight loss program that’s right for you and may or may not include prescription medication.
Your initial consultation is just the beginning. You and your provider will follow up to make sure you’re doing okay and that you’re reaching your goals. You stay on track with easy medication refills and ongoing support from your provider.
If you have questions or need assistance, the Klarity Health Patient Support team is here to help. Along with your provider, they’re committed to making sure you have the best care and support throughout your weight loss journey.
*Appointments are generally available within 24 hours. Free initial consultations are available only with select providers. Prescriptions, particularly for controlled substances, may require an in-person evaluation depending on the state of residence and current federal regulations.
The information provided in this article is for educational purposes only and should not be construed as medical advice. Always seek the guidance of a qualified healthcare professional with any questions or concerns you have regarding your health. Providers on Klarity Health are independent practitioners with clinical autonomy. Nothing in this article is intended to diagnose or treat any condition, including guaranteeing prescription medication of any kind or dosage. Not all providers on Klarity Health prescribe all medications, particularly medications that are controlled substances.
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