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Metformin vs Metformin (MOD vs OSM): What’s the Difference?

by The GoodRx Pharmacist on February 19, 2014 at 2:14 pm

Metformin and extended release metformin are used in type 2 diabetes to improve glycemic control in combination with diet and exercise. What are the advantages of extended release metformin? The extended release tablets are taken ONCE DAILY due to their slow release of the medication throughout the day. Extended release tablets are also easier on the stomach which is important for compliance when first starting a new medication.

Fortamet and Glumetza are both extended release metformin options, but because the way they release metformin over time is different, they aren’t equivalent to each other.

Glumetza is the MOD metformin product. So what does MOD stand for?

MOD stands for modified release. Glumetza utilizes advanced polymer delivery technology known as AcuForm® (for the 500 mg tablet) and Smartcoat® (for the 1000 mg tablet). It delivers the metformin to the site of absorption, the duodenum, over a time span of 8 – 9 hours. The tablet then remains in the stomach for an extended period until all of the active drug is released.

Does Glumetza have a generic?

No. Glumetza does not currently have a substitutable generic equivalent.

What is the MAX dose and available strengths of Glumetza?
Glumetza comes in 500 mg and 1000 mg extended release tablets, with a max dose of 2000 mg per day.

Fortamet is the OSM metformin product. So what does OSM stand for?

OSM stands for osmotic release. Fortamet (and its generic equivalents) use single-composition osmotic technology. When you swallow the tablet, water is taken up through the membrane of the pill, which in turn dissolves the drug in the core so it can exit through the laser drilled ports in the membrane. The rate of drug delivery is constant, and will continue as long as there is undissolved drug present in the core tablet. Once the drug is dissolved, the delivery slowly decreases and eventually stops.

Does Fortamet have a generic?

Yes: metformin ER (24 hour extended release) tablets.

What is the MAX dose and available strengths of Fortamet (metformin er)?
Fortamet comes in 500 mg and 1000 mg extended release tablets, with a max dose of 2500 mg per day.

Can Fortamet and Glumetza be substituted for one another?

NO. Glumetza has no FDA AB-rated equivalents (no other drugs have been rated by the FDA as substitutable), therefore, it cannot be substituted with any metformin generic or with Fortamet. More information on Glumetza can be found here.

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