Metformin was first approved in the US in 1995 and is now sold as a generic [1]. Getting it online is mostly about the prescription, not the pills. If you have type 2 diabetes, it's routine. If you want it for longevity, weight or PCOS, that's off-label, so expect more questions and a recent lab test before anyone writes it. What metformin is and does is covered in metformin.
Yes, you need a prescription for metformin
Metformin is a prescription-only drug in the US. Its label and packaging are marked “Rx only,” so a licensed clinician has to prescribe it and a licensed pharmacy has to fill it [1]. It isn't sold over the counter.
Any licensed prescriber can write it, in person or by telehealth, after an assessment. That includes your own doctor, an online visit, an urgent-care clinic or a membership program. Urgent care can be a fine place to start, but metformin is a long-term medicine with lab follow-up, so continuity matters more than speed.
FDA approves metformin only for type 2 diabetes
Metformin's label approves it “as an adjunct to diet and exercise to improve glycemic control in adults and pediatric patients 10 years of age and older with type 2 diabetes mellitus” for immediate-release tablets, and in adults for extended-release tablets [1]. That's the full list of approved uses.
In the large Diabetes Prevention Program, metformin lowered the rate of new type 2 diabetes by 31% compared with placebo over an average of 2.8 years in adults at high risk. Lifestyle changes did better, at 58% [2]. Preventing diabetes still isn't an approved use on the label.
Without diabetes, metformin is off-label
Prescribing metformin for longevity, weight or PCOS is off-label. A prescriber may legally do it, but it isn't an FDA-approved use, so expect them to ask why, review your history and order labs. They can also say no, especially if your kidney function or other risks argue against it.
For longevity, the case rests on animal studies and observational data. Whether it slows aging in people hasn't been shown in a trial; a large study to test the idea, called TAME, was proposed in 2016 [3]. The full evidence, including what it does to exercise gains, is in metformin for longevity. For PCOS and weight, the label says nothing, and this page makes no claim either way.
What an online prescriber will check first
Expect a health questionnaire, a list of your medicines and a recent kidney-function test. The label is specific: “Prior to initiation, assess renal function with estimated glomerular filtration rate (eGFR)” [1]. Some programs order the test for you; others ask you to bring results from your own doctor.
| Check | What the label says |
|---|---|
| Kidney function before starting | “Prior to initiation, assess renal function with estimated glomerular filtration rate (eGFR)” |
| eGFR below 30 | Contraindicated: “Do not use in patients with eGFR below 30 mL/minute/1.73 m2” |
| eGFR 30 to 45 | “Initiation is not recommended in patients with eGFR between 30 to 45 mL/minute/1.73 m2” |
| Blood counts and vitamin B12 | “Measure hematological parameters annually and vitamin B12 at 2 to 3 year intervals” |
| Contrast imaging (CT scans with dye) | Metformin “may need to be discontinued at time of, or prior to, iodinated contrast imaging procedures” |
| Alcohol | “Excessive alcohol intake” is a listed risk factor for lactic acidosis |
Metformin hydrochloride tablets and extended-release tablets, prescribing information (revised 2026) [1].
The reason for all this caution is the label's boxed warning: lactic acidosis, a rare but dangerous buildup of acid in the blood. The label lists its risk factors as kidney problems, some other drugs, age 65 or older, contrast scans, surgery, low-oxygen states, excessive alcohol, liver problems and mitochondrial diseases [1]. Your prescriber will ask about each.
Four ways to get a metformin prescription
There are four common routes: your own doctor, a one-off telehealth visit, a longevity or weight membership program, or a program that bundles labs. The table covers the online programs that sell metformin on its own. Some weight programs sell it only inside a multi-drug combination; that's a different product and isn't included here.
| Program | Visit model | Labs | Monthly price |
|---|---|---|---|
| bmiMDPartner | Questionnaire plus a telehealth visit | Not stated | $55/moMonth to month, or 3 months prepaid |
| PeterMDPartner | Consultation online or in person; a physician consultation fee applies if you're not a current patient | Not stated | $60/mo30-day plan; 60- and 90-day options |
| HealthRXPartner | Pay first, then an intake reviewed by a clinician licensed in your state | Not stated | $134/moMonthly auto-renew; longer prepaid plans |
| Found | Online health assessment with a clinician from a contracted medical group | Not included in the plan price | $162/moBilled every 28 days; longer terms available |
| AgelessRx | Online intake; a short video visit in some states | Optional paid panels | Price shown at checkoutPlan terms shown at checkout |
| Sesame | Video visit with a provider you choose | Ordered if needed | Priced per visitPer visit; the pharmacy bills the medicine |
Program details from each provider's own website [7] [8] [9] [10] [11] [12]. Found's 28-day billing means 13 charges a year. PeterMD isn't available in Alabama or Idaho. Ordered by monthly price.
If you already have a doctor who knows your history, asking them is often the simplest route. Generic metformin filled at a retail pharmacy can cost less than a program's monthly fee, because a program's price usually covers the clinician's time as well as the medicine. Programs that also prescribe rapamycin are compared in longevity prescription programs, scored, and the rapamycin route is covered in can you buy rapamycin legally.
What metformin costs online
The medicine is a low-cost generic. With an online program, most of what you pay is the clinician's time, at $25–$162 a month among the programs listed here. Check what's included: labs, follow-up messages and refills differ from one program to the next.
For a retail fill, ask your pharmacy for its cash price or check a pharmacy price tool, since prices vary by pharmacy. To turn any plan's billing cycle into a monthly cost, use the monthly cost calculator.
Fill it at a pharmacy you can trust
Use a state-licensed pharmacy. FDA's BeSafeRx page explains how to recognize a safe online pharmacy and the warning signs of sites that only look like one, and it links to a lookup for state-licensed online pharmacies [6]. A site that sells metformin without a prescription is a warning sign in itself.
When metformin isn't the right call
The label rules metformin out for people with severe kidney impairment (eGFR below 30), with acute or chronic metabolic acidosis, including diabetic ketoacidosis, or with a prior allergic reaction to metformin [1]. Starting it isn't recommended at eGFR 30 to 45.
There's also a trade-off for active people. In two trials of older adults, metformin blunted gains from exercise: it reduced the improvement in insulin sensitivity and VO2 max after 12 weeks of aerobic training [4], and it reduced muscle growth from resistance training [5]. If staying fit is part of your longevity plan, raise this with your prescriber. More is in metformin for longevity and rapamycin.