I had no clue about this, so now I am curious! Send in the gurus!!

Oh Boy another side effect.

My big shocker was the effect that Neurontin had on my lungs. I stopped taking it last year and haven't had bronchitis or pneumonia since!

nutrient depletions over time.

Not all have been studied (some of the newer ones)...but
Tegretol for example depletes,
folic acid
Vit D
Calcium
biotin

Phenytoin (Dilantin)
The above 4
plus
Vit B1 (thiamine)
Vit B12
Vit K as well.

Folate in particular seems antagonistic to the seizure control the drugs provide..so physician supervision should be had for adding folic acid in particular with AEDs.
Some physicians will generalize with the newer agents, but that is just
an extension of concern without evidence.

Vitamin D is getting alot of attention in the past year or so... take a look
at our Vitamin/Mineral forum for links on information.

All seizure patients should have a bone density scan and repeat it once a year or so if on meds, just to be sure.

Many many drugs for other uses, also affect nutritional status. If you visit our forum here, you can post to me other drugs, and I will look that up for you.
Or in PM if your prefer privacy.