Please help my gerbil!

Question
I have a gerbil who has not been doing well for a while.  At first I just thought he slept a lot, but I got concerned so when I took him out, he was nothing but skin and bones!  You could even feel the vertebrate on his tail!  I freaked out!  I have force fed him some vitamin water, and have gotten him to eat a couple of sunflower seeds so far.  He won't seem to eat anything else but those.  This evening when I got off from work, I noticed that one of his eyes wasn't open barely at all.  I checked on it and it was glued shut with red gunk. I know that gerbils tears and snot are red, but this seemed different.  I have  another gerbil that suffers from bloody noses and this was not the same.  I took a warm q-tip and separated his eye and then he went back up to bed!  Please help me with what could be wrong!  I love gerbils so much, and would be devastated to see him not make it!  Thank you in advance!!

Answer
If this gerbil has not been doing well for a while and he is now skin and bones he is most likely dying. You need to get him into a vet if you have not done so already. I am not an expert on gerbils since they are illegal here in California so we don't even work on them.
He really needs to be seen by a vet and probably so a week ago.
I am sorry that he is doing so badly.