It hasn't increased my appetite, which most meds have done while being on them, maybe for you it is just the initial dosing, I have been on 200mgs for almost 2 years.
But I did have my thyroid re-checked after weaning off Lithium (is a wonderful med for mania) and it did show underactive.
Between being on thyroid (synthroid) and Lamictal I feel 100 percent better, just dealing with family situations (long story) is still the problem, but as far as myself I am functioning, even laughing and smiling more
Now if you want to know what made me get fat fast was, Depakote, was on it for a year and had gained nearly 30 lbs., lost 20 over the 2 years of being on Lamictal.
Give it awhile, the drowsiness doesn't linger much at all, though again I realize meds affect everyone different.
In fact Lamictal and when I was on Lithobid, I was able to drive and stuff without falling asleep, where Depakote caused me 3 times to fall asleep at the wheel, so I told my pdoc I no longer wished to use it.
Lithium and Depakote do require periodic blood tests to be assured liver, kidney, and thyroid function are not being jeapordized, the Depakote blood monitoring I had was once a month for (liver) function, with the Lithobid it was every 3 months after first being put on it it was once a month and then just every 3 to 6 months, not bad, beats every month.
Give the Lamictal time, it is good too cause I was able to stop Celexa, Lamitcal addresses the depression part of bipolar than the others while still being a mood stabilizer.
Now that I chewed your ear off, I'll step down from my soapbox and send you my good wishes
Take care,
DE

In giving advice seek to help, not please your friend
SOLON