The XR in LAMICTAL XR stands for extended release. This means the medicine is released slowly into the bloodstream over a longer period of time than a medicine that is released quickly, like LAMICTAL (lamotrigine). The extended release allows LAMICTAL XR to be taken just once a day.

Prescription LAMICTAL XR is a once-a-day medicine used to treat partial seizures in patients 13 years of age and older.