This article was originally written by the Sequence clinic team (now known as WeightWatchers Clinic).

How effective is Metformin for weight loss?

Published July 14, 2024

Metformin may be a good choice for those looking to lose weight and treat their obesity. But there are some things you should know before taking Metformin for weight loss, including common side effects, clinical study results, and cost.

In this article, we’ll answer the following questions:

What is Metformin?


Metformin is a generic medication that is FDA-approved for the treatment of type 2 diabetes and sometimes used off-label for weight loss and weight-related conditions.

How does Metformin help you lose weight?


There are many hypotheses about how Metformin works for weight loss. The exact mechanism isn’t known, but most patients report a slight appetite and craving benefit. This change in appetite and cravings helps patients eat fewer calories overall, which leads to weight loss.

‍Some studies suggest that Metformin has a positive effect not only on appetite regulation but also the gut microbiome.

What do studies say about Metformin?


There are multiple studies exploring Metformin for weight loss and obesity treatment. One study from 2013 found Metformin to be effective for weight loss, particularly in those with insulin resistance. Similarly, other researchers have found Metformin to be effective for weight loss in patients with PCOS.

What are the most common side effects of Metformin?


The most common side effects for Metformin are gastrointestinal side effects including nausea and loose stools. We recommend you take it in the evening and avoid taking it with a high-fat meal (like meals with a large amount of butter, cream, eggs, or cheese) to minimize the risk of side effects. The tablets should not be chewed or crushed. Please alert your clinician if you experience severe diarrhea. Similar to the GLP-1s, these side effects usually go away over time as your body adjusts to the medication.


How much does Metformin cost?


While generally not as powerful as a GLP-1 medication for weight loss, Metformin is usually more affordable for cash paying patients (often under $30 per month). This is because Metformin is a generic medication.

Many insurance companies also have Metformin on their formularies as a step-up medication for GLP-1 medications like Wegovy. This means that your insurance may require you to try Metformin before you’re eligible for insurance coverage on a different medication.

How can I use Metformin?


Take one tablet once daily. Be as consistent as you can with dose timing. Taking Metformin with meals can help reduce side effects.

Swallow the tablet or extended-release tablet whole with a full glass of water. Do not crush, break, or chew it.

How do I get a prescription for Metformin with WeightWatchers Clinic?


Your WeightWatchers Clinic weight management treatment plan will vary depending on your medical history, goals, and insurance coverage. Clinicians may prescribe a medication like Metformin off-label given its proven weight loss results.

If you’re looking to get evaluated for a obesity treatment prescription, we’ll need a bit more information. Every member must match recommended medical criteria, meet with a Clinician, and discuss their medical needs to make sure pharmacological treatment is appropriate.


This content is for informational purposes only and does not constitute medical advice, diagnosis or treatment. It should not be regarded as a substitute for guidance from your healthcare provider.