HELP! We just noticed today that one of our hens is severely sick. Her eyes are half way shut, she’s breathing heavy, won’t drink/eat, doesn’t respond as fast (let me pick her up and none of my chickens are that friendly), lack of going to the bathroom, and trouble standing/laying a lot. Any suggestions?
Hi
@Animalsanctuary10 
Welcome To BYC
If you have vet care, that is always best.
How old is your hen?
When is the last time she laid an egg?
Photos of the hen so we can see her condition may be helpful
If she is not pooping at all, I would check to make sure she is not egg bound. Glove up, get some lubricant and feel inside the vent about 1-2" - see if there is an egg in there.
If she has an egg in there, you can try soaking her in a warm epsom salts bath to see if that will help her along. Please note, a hen that is sick and lethargic, soaking them may stress them or send them over the edge.
Alternatively, you can place her in a steamed up bathroom or place her on a towel covered heating pad set on low. Monitor her closely that she does not overheat if she is not able to move away.
Hydration is important so do the best you can to get some fluids into her. Calcium can help if they are egg bound, if she is unresponsive, that may be hard to do. Crushed Tums or 1/2 caltrate will do for Calcium.
Let us know what you find out once you check her, photos are always welcome.