yes please get your gecko to a vet. closed eyes usually means dehydration. Do you have a small eyedropper? maybe mix some water (and alittle vitamins) together, not a paste, but shoot some down his/her throat. keep your leo hydrated. if you start seem her resting in her/his water dish, then that's a really bad sign of dehydration, and it's hard to bring them back at that point. Does she have fat on her tail (a decent amount) if so, consintrate on rehydrating her between now and the vet visit. see if you can get her to drink 2-3 droplets every 4 hours. i wouldn't give her much than that.
I took a moment to look at one of my books, here's a bit of info i found
"as with all reptiles, cool temps for excessive periods of time can cause immune system supression with subsequent respritory infections.Symptoms may be subtle and include a partial opening of the mouth with a LABORED EXPIRATION. Initally, a temp change to a day tiem high of 84/86F with a drop to no lower than 80F may be adequate for mild cases. if improvement is not seen or symptoms worsen, vet should be seen."
So try turning up your temps in your cage, we are approaching cooler weather and I understand that you have had the same setting in your cage for awhile. But think of elderly people, for many years when they were younger people they were more adaptable to temperatures, now they are a bit older, it's a bit harder to regulate the body temperature. The fact that your gecko is going back and forth between warm/cool reminds me of hot/cold flashes of when someone gets sick.
does your geco have diarrehea?
for getting your geckot o eat, go to the foodstore and pick-up some turkey flavored baby food, mix some viatmins in with the food and use the dropper to feed small meals to your gecko, twice a day. don't over feed (even if it seems like they are accepting the food well) because if your gecko is having issues it's probably going to be very easy to upset their tummy. if they start vomiting it's going to make them more dehydrated
so basic just:
get your gecko hydrated (most important) and get it to the vet. turn up the temps on your cage and try baby food (turkey flavor). if that doesn't work (baby food) use mealworm guts
i wouldn't reccomend feeding your gecko crickets or full bodied mealworms right now, might upset their tummy. just gutload your bug like normal and pinch their headoff and squeese onto gecko's lips. let them lick it up. do maybe 3-4 of these, twice a day.
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