Dear doc, I have been diagnosed seizure disorder 2007. I have been prescribed 25mg lamictal once a day for 2 weeks. What will be my next dosage?

Lamictal dose. You should start with a low dose just to see if you have a sensitivity to lamictal. If there is no skin reaction, the dose will be gradually increased weekly by 25 mg. You should certainly check with you neurologist to decide on the max dose.
Crystal ball time? 25 mg of Lamictal for an adult prescribed as single drug is a minute dose. If you are taking valproate also, then such a low dose might be an appropriate starting place. But why ask healthtap when you should be asking your neurologist? No neurologist? Get one.