Ascorbic acid vitamin c symptoms and conditions

Hello! I've been taking Lamictal for about 6 years now. I'm diagnosed as BP II and have the most difficulty with depression. I currently take 500 mg-- 400 mg at night and 100 mg in the morning. I have to say that Lamictal has been very good to me for the most part. As long as I don't put myself into extremely stressful positions-- such as my last job-- I do quite well. I also take a combination of supplements with Lamictal which seem to give the extra push that I needed to completely get out of my last depression. I take 1000 mg EPA (fish oil), B-100 Complex, Folic Acid, Cal-Mag, multivitamin (high quality, organic), Vitamin D (at least 1000 mg) and a few others.

I notice that when I take it at night if I don't go to sleep right away, my mouth and tongue will tingle. Sometimes when I take it in the morning, I feel foggy and dizzy and sometimes get vertigo. Every now and then the side effects seem to get worse, which I am not sure about. I started searching on the internet because I've been noticing that the "tip of the tongue" problem has been occurring more and more often. I often cannot think of the word I want, simple things even. As others have mentioned, I also have difficulty with memory. I am still very successful, currently pursuing a 2nd Master's Degree, but have noticed that achieving the same level of quality of work takes a lot more effort than during my previous degrees.

I do have some periods of anger/irritability and have recently been sleeping a lot, though it probably has a lot more to do with the time of year-- winter with less light-- than anything else.

I am particularly worried about my memory loss and inability to sound "well-spoken" in a setting which demands that of me. It is frustrating! I don't want to do any lasting harm on my brain. After increasing to 500 mg from 400 mg, I have noticed more of these brain issues, but I'm also doing so much better mood wise!