A quick search through Reddit reveals several wondering if birth control can drain their energy. "I’ve been on Mercilon for over two years now and have had little to no problems with it except for feeling crabby a week before my period," one woman wrote . "Lately however, I’ve just been feeling extremely tired and demotivated. Even after getting a good night’s rest I wake up feeling tired, demotivated and my brain feels foggy? I’m not sure how else to describe it. This feeling usually lasts the whole day and it feels impossible to shake. Has anyone else experienced this? Could it be a side effect of my birth control?"