I looked at WonderBoy's site, as well as looking at one of the documents on the FDA site. Tremors is definitely a side effect. From what I can tell, your son is on a low dose (the one document I looked at < http://www.fda.gov/cder/ogd/rld/20241s14.PDF > said normal maintenance for patients 2 - 12 is 5mg/kg/day to 15mg/kg/day. If I calculated correctly, for a 52lb boy, that's 118mg per day at the 5mg/kg/day rate, and you're doing 100mg/day. Table 9, page 25, as listed on the page.)

I'm not sure what kind of advice to give you. I don't know if increasing Lamictal will decrease the tremors, but since it sounds like Lamictal is the reason for the tremors, increasing Lamictal seems kind of contra-indicated. I suppose you weren't getting the seizure control you wanted at the lower dose, and that's why you were increasing the nighttime dose, before this all happened.

(((Hugs))) Seizures suck. And playing med change games is no fun either.