Getting on metformin typically starts with a conversation with a healthcare provider, either in person or through a telehealth platform. Metformin is a prescription medication, so you can’t buy it over the counter. But it’s one of the most commonly prescribed drugs in the world, it’s inexpensive, and providers are generally familiar and comfortable with it. The path to a prescription depends on why you need it and what your current health looks like.
What Metformin Is Prescribed For
Metformin is FDA-approved specifically for type 2 diabetes in adults and children age 10 and older. It’s meant to be used alongside diet and exercise to help control blood sugar. In clinical trials, patients taking metformin saw their fasting blood sugar drop by about 60 mg/dL and their HbA1c (a measure of average blood sugar over three months) drop by roughly 1.8% compared to placebo.
Beyond its official approval, providers regularly prescribe metformin off-label for a few other conditions. Polycystic ovary syndrome (PCOS) is one of the most common. Prediabetes is another, where the goal is preventing a full progression to type 2 diabetes. Some providers also prescribe it to help with weight management in people with diabetes or insulin resistance, since metformin can prevent weight gain or promote modest weight loss. More recently, there’s been growing interest in metformin as an anti-aging drug. Observational studies suggest people with diabetes who take metformin may actually have better survival rates than some non-diabetic controls. A large trial called TAME (Targeting Aging with Metformin) plans to enroll 3,000 people aged 65 to 79 to test whether metformin reduces age-related diseases in people who don’t have diabetes. Until those results come in, prescribing metformin purely for longevity remains speculative.
What Your Provider Will Check First
Before writing a prescription, your provider will want blood work. The two key tests are fasting blood glucose and HbA1c. For a type 2 diabetes diagnosis, the threshold is a fasting glucose of 126 mg/dL or higher, or an HbA1c of 6.5% or above. Prediabetes falls in the range of 100 to 125 mg/dL fasting glucose or an HbA1c between 5.7% and 6.4%.
Kidney function is the other critical checkpoint. Your provider will measure your estimated glomerular filtration rate (eGFR), which tells them how well your kidneys are filtering. The FDA has set clear cutoffs: metformin should not be started if your eGFR is between 30 and 45, and it’s completely off the table below 30. If you’re already taking metformin and your kidney function drops below 45, your provider will reassess whether to continue. These thresholds exist because impaired kidneys can allow metformin to build up in the body, raising the small but serious risk of a condition called lactic acidosis.
Your provider will also ask about liver health, heart failure, and alcohol use, since heavy drinking combined with metformin increases the risk of that same lactic acid complication. People with mild to moderate liver or kidney problems may still qualify but at a reduced dose.
How to Bring It Up With Your Provider
If you think metformin might be right for you, being direct works best. Mention the specific reason you’re interested. If you have a family history of type 2 diabetes, bring that up. If your last blood work showed borderline blood sugar numbers, reference those results. If you’ve been diagnosed with PCOS and are dealing with insulin resistance, say so. Providers respond well to patients who come prepared with their own health data and a clear reason for asking.
If you’re interested in metformin for weight loss or longevity without having diabetes or prediabetes, be upfront about that too. Some providers will prescribe it off-label if you have relevant risk factors like insulin resistance. Others will want to see blood work that justifies it. The conversation goes more smoothly when you frame it around specific health concerns rather than simply asking for the drug by name.
The Telehealth Option
You don’t necessarily need an in-person visit to get metformin. Telehealth platforms can prescribe it after a virtual consultation. The process typically involves submitting a photo ID, your medical history, a list of current medications, your insurance details, and your pharmacy preference. A provider then reviews your information during a video or messaging-based visit. For a new prescription, they’ll evaluate your symptoms, history, and recent lab results. If you don’t have recent blood work, most telehealth providers will order labs before prescribing.
Telehealth can be especially convenient for straightforward cases like prediabetes or PCOS where the diagnosis is already established. The prescription is sent directly to your pharmacy, and the whole process can sometimes wrap up within a day or two.
What to Expect When You Start
Metformin comes in two main forms: immediate-release tablets (taken two or three times a day) and extended-release tablets (taken once daily, usually with dinner). The standard starting dose for the extended-release version is 500 mg once a day. From there, your provider will typically increase the dose by 500 mg each week based on how your blood sugar responds and how well you tolerate it. The maximum dose for extended-release is 2,000 mg per day.
Stomach issues are the most common side effect, especially in the first few weeks. Nausea, diarrhea, bloating, and gas are typical as your body adjusts. This is where the extended-release version has a clear advantage: it releases the drug more gradually in the upper digestive tract, and clinical trials show significantly fewer GI side effects at both three and six months compared to the immediate-release form. If you’re prone to stomach sensitivity, it’s worth asking your provider specifically for the extended-release version.
Taking metformin with food also reduces stomach problems. Most people find that the GI side effects fade after the first few weeks, especially if the dose is increased gradually rather than all at once.
Cost and Availability
Metformin is one of the least expensive prescription medications available. It’s been generic for decades, and a month’s supply often costs under $10 even without insurance. Most pharmacies stock it routinely. If cost is a concern, discount programs and pharmacy coupons can bring the price down further. The combination of low cost, wide availability, and a safety record spanning over 60 years is part of why metformin remains the go-to first-line treatment for type 2 diabetes worldwide.