Definition: An extended-release tablet (often marked XR or XL) is built to let the drug out slowly over many hours, so it can be taken less often, such as once a day. Labels for these tablets usually say to swallow them whole, because crushing, cutting or chewing can break the slow-release design.
| Product | What the label says |
|---|---|
| Xigduo XR (dapagliflozin and metformin) | Once daily in the morning with food; swallowed whole and never crushed, cut or chewed |
| Glucotrol XL (glipizide) | Once daily; the drug sits inside a shell that does not dissolve |
Synjardy also comes as Synjardy XR, taken once daily instead of twice. Xigduo XR pairs dapagliflozin with extended-release metformin, so the whole combination tablet is taken once a day. The slow design is what lets a label set a once-daily schedule for a drug that would otherwise be taken more often.
The Glucotrol XL label says the empty shell may pass in the stool after the medicine is absorbed, and that this is normal. Because the shell does not dissolve, the label also says to avoid it with severe narrowing of the gut, after blockage was reported with another drug in this design.
Immediate-release and extended-release versions of the same drug are taken on different schedules. Log the full name, including XR or XL, so the timing in your history makes sense. The slow release also changes the Tmax, the time to peak level.
Read more on Dose Track: Xigduo XR side effects · Glucotrol XL side effects · Synjardy side effects · Glimepiride vs glipizide