I've been on Sertraline twice - once for about 18 months three or four years ago, and started it again just after Christmas. This second time I didn't get the side effects of tiredness but since I was ill a few weeks ago I've felt completely and utterly exhausted. It feels like a different kind of tiredness to usual - I just want to sleep and have no energy and am yawning a lot but don't feel like I've done anything that should mean I'm physically tired. Is this normal?