Short answer: Both pair pioglitazone with a second diabetes drug for adults with type 2 diabetes. Duetact adds glimepiride, a sulfonylurea, and is taken once daily with the first main meal.1 Actoplus Met adds metformin and is taken with meals, up to three tablets a day.2 Both carry a heart failure boxed warning; Actoplus Met's also covers lactic acidosis. Neither label compares the two.
| Duetact | Actoplus Met | |
|---|---|---|
| Partner drug | Glimepiride, a sulfonylurea1 | Metformin, a biguanide2 |
| Strengths | 30 mg pioglitazone with 2 mg or 4 mg glimepiride1 | 15 mg pioglitazone with 850 mg metformin2 |
| How taken | Once daily with the first main meal1 | With meals; one tablet once daily to start, or once or twice daily if already on metformin2 |
| Maximum a day | 45 mg pioglitazone and 8 mg glimepiride1 | Three tablets: 45 mg pioglitazone and 2,550 mg metformin2 |
| 24-week trial | Pioglitazone 30 mg with a sulfonylurea: low blood sugar 13.4%; weight gain 9.1%1 | Actoplus Met 15/850 mg twice daily: diarrhea 9.0%; headache 5.5%2 |
| With strong CYP2C8 inhibitors such as gemfibrozil | Switch to separate tablets; pioglitazone limited to 15 mg1 | At most one tablet once daily2 |
| Missed dose | Take the next dose as prescribed; never two doses the next day1 | Take the next dose as prescribed; never two doses the next day2 |
| Boxed warning | WARNING: CONGESTIVE HEART FAILURE1 | WARNING: CONGESTIVE HEART FAILURE and LACTIC ACIDOSIS2 |
The pioglitazone warnings are shared: heart failure, swelling, liver failure, a possible link to bladder tumors, more fractures in women (5.1% vs 2.5% on placebo in PROactive) and swelling at the back of the eye. Neither is started with NYHA Class III or IV heart failure.12
Duetact's glimepiride adds severe low blood sugar, serious allergic reactions, red blood cell breakdown and the sulfonylurea heart-death class warning.1 Actoplus Met's metformin adds lactic acidosis and low vitamin B12; it is not used with an eGFR below 30 and is paused around some contrast scans.2 These numbers come from separate trials with different people, lengths and methods, so they are not a head-to-head comparison.
Which, if either, fits is for your prescriber. More detail: Duetact side effects, Actoplus Met side effects, the Duetact and Actoplus Met dosing schedules, the Duetact and Actoplus Met missed-dose pages, the pioglitazone, glimepiride and metformin guides, and Actoplus Met vs Actos: what does adding metformin to pioglitazone change?.