Venlafaxine
"I've been taking this medication for several weeks now (Effexor XR 37.5mg daily) and it has helped me a lot more than the Celexa I was on. 

Although recently (within the last 10 or so days) I have experienced very mild headaches that last a long time and feeling fatigued all day. Caffeine doesn't help and extra sleep doesn't help. 

I've had problems with fatigue all my life but this feels different. I am not sure if this is related to the medication because I have not had any side effects and I've been on this medication for almost a month now."