I'm up to 50 mg of Lamictal and it's been nearly two weeks. Next week I go up to 100 mg and I'm wondering when the symptoms of depression will lessen?

Longer. Lamictal is a seizure medication used to prevent the depression in future cycles of Bipolar depression. However, it's not an antidepressant for the acute part of depression. Therefore, your doctor may need to treat you with another antidepressant until the depression subsides .