Prozac - a patchy 7th week

I've noticed something odd this week, the Prozac seems to work when I really need it to but doesn't maintain a constant effect. For example, at a Sunday lunch with friends I found myself unusually chatty and sparky when first meeting up, making a special effort with folks I didn't know so well, then ran out of steam by dessert and felt ready for bed by early evening. It's the same at work; the brain copes admirably with the daily mental and practical tasks (ok, we'll ignore the tedious 3 hour meeting I nearly fell asleep in several times) but as soon as I reach the end of my list of things to do, it's as though someone has pulled the plug and I grind to a halt. I could just go to sleep now and may have to catch a quick nap soon as it's going-to-the-pictures-with-best-friend-night. On top of that, the reduction in stress levels still doesn't seem to have brought about an improvement to my skin, if anything the eczema is even worse. Thank goodness it's mostly out of sight. Have started taking a multi-vitamin tablet to see if that helps.