I've been on Tegretol for 16 years. I get blood tests done every 3 months. I have been having issues with red blood cells and anemia. My doc wants me to consider changing medication due to the negative long term effects of tegretol. Tegretol affects bone marrow cells over many years of use. I use it for Bi Polar.

For short term use, the blood levels help the doc find a theraputic level so you have enough in your system.