I was started on Teg from the beginning of my seizures after the operation. It had not been on the market that long and was considered a new drug (1981) at the time. Due to having 6 yr old (me!) complaining about the taste of the chewables; I was changed over to the 200mg tabs within 2 weeks (about when I turned 6).
Teg is the only drug I have *not* been able to get off for my treatment. Only form I have not been administered was syrup... and from what I have been told I'm lucky! I've had the XR's (Teg Retard called acros the pond); have NOT been on it's close relative Carbatrol. Some patients were switched over when there was a mass shortage of Teg XR (has it been 2 years already?) a few years ago.
I will say this, not sure if it will help give you insight or not. After highschool; around when I was to be starting college my seizures spiraled downhill after being controlled. I had a drivers license and could drive without restrictions. Then control was lost. They added Dilantin, then Depa, took away Dilantin, Added Lamictal, added back Dilantin, Switched me to TegXR, Tried removing TegXR, Then came Keppra, Zonegran, Topamax...
You see the rollercoaster I was riding with medications. Basicly my chaos started after I had almost full control all those years. It took until I was placed on my current mix to reach a good balance. 3-5 months without seizures usually. However I no longer have my pre-cursors, or "warnings" before a larger seizure strikes.
For somebody in your shoes I'd strongly recomend doing what I did after a few Dr fowl-ups. When they change me, or suggest a new med; I pull the FDA write-up on that drug off the web. It may be 10 pages of technical headache; but it's the information I want. Not the one page abreviated the pharmacy hands out. This way I KNOW what I'm getting into and if I need to avoid anything, what the warnings are, what is normal, if I need to drink more water or avoid some foods etc.
My Dr loves me for researching me meds. He told me I am one of the few patients he does not have to be concerned about. He knows I'll call if I have problems or don't feel correct. How many times can you cut off your Dr when being explained your new med and keep the line word for word being you have read the text earlier at home? It made my Dr laugh. Also made him confident not to worry about me on the new med.
My previous Dr did NOT like me for being educated on medications more than he was (he had me on a 3 drug mix that a patient should never be on). Like I said. Being informed as a parent or patient always helps!