I've been having trouble lately with a lack of strength in my right hand. It comes and goes, and it tends to be worst in the mornings, when I sometimes find I can't open jars or hold a cup with that hand. It's not a new thing; I started getting it from time to time in my mid teens, but it's been worse than usual for the past couple of months. My left hand is affected to a lesser degree, and although I'm right handed, I sometimes switch to using my left hand when I don't have enough strength in the right one.