There's reason why Topamax is called Dopamax.

It really, really slows you down. I've been on lamotrigine for 3 years. Yes, it really lifted my depression, but it has also made me stupid. I lost 2 jobs because of the cognitive difficulties that lamotrigine has caused. Since I lowered the dose, the cognitive symptoms have lessened but have not gone away. I've decided to get off this medicine once this school term is over whether my doctor likes it or not. I don't know why doctors say that anti-epileptic drugs don't cause cognitive problems when the drug is designed to slow down brain activity... Hello? Duh!
I don't remember yawning on Celexa but I did yawn like crazy on Lexapro until noon even though I wasn't tired. Lexapro is a refined version of Celexa. It has a lot more active ingredient in it. Lexapro worked better for my depression and made me less drowsy.
Whatever you do, don't stop cold turkey or you will be in a world of hurt.