In other areas of the world, there is also Obimet, Gluformin, Dianben, Diabex, Diaformin, Metsol, Siofor, Metfogamma and Glifor. There are several formulations of Metformin available to the market, and all but the liquid form have generic equivalents. Metformin IR (immediate release) is available in 500-, 850-, and 1000-mg tablets, while Metformin XR (extended release) is available in 500-, 750-, and 1000-mg strengths (also sold as Fortamet, Glumetza, and Glucophage XR in the US). The use of an extended release formulation is to counteract common gastrointestinal adverse effects, as well as to increase compliance by reducing pill burden and therefore can improve adherence, at the expense of the pills larger size. Also available is liquid metformin (sold only as Riomet in the US), where 5 mL of solution contains the same amount of drug as a 500-mg tablet. The use of a liquid form can be beneficial in helping those with physical or psychological swallowing problems take the medication, or to potentially reduce the number of steps needed to take the medication. Combination with other medications
When used for type 2 diabetes, metformin is often prescribed in combination with other medications. Several are available as fixed-dose combinations, with the potential to reduce pill burden, decrease cost, and simplify administration. Thiazolidinediones (glitazones)
Rosiglitazone
A combination of metformin and rosiglitazone was released in 2002, and sold as Avandamet by GlaxoSmithKline, or as a generic medication. Formulations are  500/1, 500/2, 500/4, 1000/2, and 1000 mg/4 mg of metformin/rosiglitazone.
Pioglitazone
The combination of metformin and pioglitazone (Actoplus Met, Piomet, Politor, Glubrava) is available in the US and the European Union. DPP-4 inhibitors
Dipeptidyl peptidase-4 inhibitors inhibit dipeptidyl peptidase-4 and thus reduce glucagon and blood glucose levels. DPP-4 inhibitors combined with metformin include a sitagliptin/metformin combination (Janumet), a saxagliptin/metformin combination (Kombiglyze XR, Komboglyze), and an alogliptin/metformin combination (Kazano, Vipdomet).Linagliptin combined with metformin hydrochloride is sold under the brand name Jentadueto. As of August 2021, linagliptin/metformin is available as a generic medicine in the US.SGLT-2 inhibitors 
There are combinations of metformin with dapagliflozin, empgaliflozin and canagliflzoin. Sulfonylureas
Sulfonylureas act by increasing insulin release from the beta cells in the pancreas. They often can be used as secondary therapy if metformin alone is not sufficiently effective at reaching normal blood glucose levels. Metformin is available combined with the sulfonylureas glipizide (Metaglip) and glibenclamide (US: glyburide) (Glucovance). Generic formulations of metformin/glipizide and metformin/glibenclamide are available (the latter is more popular). Meglitinide
Meglitinides are similar to sulfonylureas, as they bind to beta cells in the pancreas, but differ by the site of binding to the intended receptor and the drugs affinities to the receptor. As a result, they have a shorter duration of action compared to sulfonylureas, and require higher blood glucose levels to begin to secrete insulin. Both meglitinides, known as nateglinide and repanglinide, is sold in formulations combined with metformin. A repaglinide/metformin combination is sold as Prandimet, or as its generic equivalent.