Welcome to Just Answer! I would like to help you and your cat with this question, but need a bit more information, please.
When did this start?
Is she sneezing or coughing at all?
Any discharges from her eyes or nose?
Is she indoors only or does she go out?
Anything stressful in her life in the last few weeks (a visit to the groomer, the vet, or a boarding facility, a move)?
Is she eating and drinking?
Any vomiting or diarrhea?
What are her energy levels like?
Thanks for that further information!
There are many things that could cause your cat's third eyelids to be prolapsed (which is what you are describing). This happens any time the cat is dehydrated or feels unwell. So, it doesn't tell me what she is feeling unwell due to - but you have also mentioned lethargy, congestion, one cough, and what sounds like a decreased appetite.
My top concern would be that your girl is in the early stages of an Upper Respiratory Tract Infection. URTI's are caused by a virus (usually Rhinotracheitis which is a Herpes virus, or by Calici virus). Since antibiotics do not kill viruses, only bacteria, they will not help your cat get over this viral infection. Antibiotics are only helpful if she gets a secondary bacterial infection on top of this viral infection.
She may have a Herpes viral infection, which can flare-up any time she is stressed. If she had "snuffles" and sneezes as a kitten, that could have been a Herpes virus causing it. As with humans, once a cat has a Herpes virus infection, they have it for life (though it is not contagious to humans!). It goes into "remission" and only flares up when the cat is stressed and her immune system is diminished.
So, what can you do to help her?
Lots of things!
1. Encourage her to eat. Good nutrition will give her body the energy it needs to fight this infection. As with us when we have a cold, when the nose gets stuffed up food loses its flavour. So, you can offer her some canned food (particuarly the fish flavours as they are particularly strong smelling) which has much more smell than dry. Also, you can warm the food up a little in the microwave as warm food smells more than cold.
2. Encourage her to drink. What you can do is try to get some calories into her in a liquid form - that way she is getting nutrition at the same time as fluids.
I suggest opening a can of tuna *in water* and offering the liquid.
Also, you can pick up Clam Juice in most grocery stores (sold in with the V8 or the canned tuna) and mix that with some water.
You could try Lactose Free milk (Lactaid is the Canadian brand). Whiskas makes a tetra pack of "Kitty Milk" that is lactose free milk with flavouring added.
You could try getting some human baby food in meat flavours (check that there are no onions or garlic in the ingredients) and mix that with warm water and offer that, or syringe it in little bits into your cat's mouth.
Offer her some canned cat food, and mix it with water to make a slurry if she won't eat it.
Boil a chicken breast and then put it in the blender with water to make a baby-food consistency gruel to offer.
You could pick up nutristat http://www.agri-med.com/site/255063/product/NUTRST-4.25 It is a calorie-dense paste that you can syringe into them to get maximum caloric impact from a given volume of food.
Here is another link to ways to encourage cats to eat:
It has some good suggestions.
I'm afraid you may have to force feed her with a syringe. The human baby food (or making your own puree with cooked chicken breast in a blender with lots of water) goes through a syringe quite well.
3. Clean her nose. You can put a bit of warm water on a washcloth, wring it out, then hold it on her nose (if she'll let you) to soften any dried mucus so it comes off.
4. Steam her. Take your kitty into the bathroom while you run a hot shower for 15 minutes. The hot, steamy air will help to loosen any nasal secretions so she can sneeze the mucus out and clear the airways. Doing this twice a day would be great! You could offer her some canned food while the shower is on so she didn't get too frightened.
5. Put drops in her nose. Just go to the pharmacy and ask for opthalmic saline, or have a look in the contact lens section. What you want it just sterile saline drops to relieve dry eyes - NO medication in it. The pharmacist should be able to point it out to you. Put one drop in each nostril twice daily. The idea is that you are helping to moisten the area so your cat can sneeze out any congestion in there. Continue for a week.
Depending on which virus your cat has (Herpes or calici) this infection could take 1 - 4 weeks to clear up. If you can do nothing else, giving her the canned food is going to make the biggest difference in how well she does with this. Her body just needs that extra energy to fight this. Also, the first ingredient in canned food is water, so it is a way of making sure she is getting a bit more fluid.
I'll give you some links to further information:
Good luck with her! She is lucky to have someone looking out for her!
If you feel that this has been helpful, please hit the green "Accept" button. I will still be here to provide more information if you need it.