Hi there, are you taking lithium alone? I get the same thing - my irritation gets worse as the day goes on and late afternoon can skyrocket into a full blown meltdown. I found that if I take my lithium before bed and my other med (abilify) in the morning, I'm a little more leveled out. I dont know if this is an option for you, but it might be something to talk to your dr about. I know how you feel and I'm sorry this is happening to you, it's not fun. I'm also very sensitive to meds and can't tolerate a lot and so it's a bit of a tight rope walk trying to figure everything out. Let me know how it goes okay?