Sick Baby Chick

[newchickmomma2020]

So I got these chicks from Rural King Sunday.... theyre all doing great except one whose had some manure stuck to her butt.... I cleaned it off with warm water and a towel but the chick is still really lethargic and just sitting in the brooder and not really being active like the other chicks... any advice is welcome.
They are eating chick starter that is medicated... do they need anything else, should I quarantine this little chick from the rest? Im new to chickens so not sure what to do.

 

[azygous]

If you could post a photo of this baby chick, we could then see how old it is and get a look at its posture and eyes which will in turn give us information about its state of health.

Meanwhile, give this chick a little warm sugar water with a tiny pinch of salt and baking soda.

How many chicks?
What are the dimensions of your brooder?
Measure the temperature right under the heating light on the floor of the brooder if that's what you're using for heat. Measure the temperature on the floor farthest from the heat source.