I think lamictal is only approved for children with epilepsy. It would be a good idea to consult a psychiatrist. Usually lamictal, antipsychotics and other drugs (like lithium, T3 hormone, trazodone, buspirone, ) are augmentation strategies for treatment resistant patients not first line choices.
For SAD and MDD (Major depression disorder) Moclobemide appears safer than Lamictal for instance, but most guidelines would recommend trying another SSRI (like fluvoxamine or fluoxetine), switching to another class (like Milnacipran) and only if that fails you could perhaps see with your doctor about augmentation(2 or more drugs). Since it's a kid drug interaction and side effects should be carefully studied