Tell us a little about the geckos environment- heat, lighting, availability to water. How long have you had the gecko, and was it healthy for a long period of time in your care before becoming ill>
Here are some things you can immediately do:
1. Check the poop. Sounds gross but this is the best way to tell if you have a sick gecko or not.
Is it firm and dark? Is it wet/stinky/grey or light colored? You certainly have a problem if it is wet, sticky or light colored.
2. Make sure the gecko has access to the correct temps (enclosure should be at least 78 to 84 with a warm spot in the upper 80s. It should also have a hide in the warm and cool sections of the enclosure. The light should be on only during the daytime. Right now many people 'cool' their geckos and drop the temps to the low 70s. The gecko will not eat nearly as much as usual. However, they will not decrease in size (especially the tail) all that much.
3. Water. Make sure you have a water dish in the enclosure and that it has fresh clean water every other day.
Right now, your gecko is probably dehydrated. Frequently mist the enclosure (only if the temps are correct) so that the water evaporates every 4-6 hours.
4. Feeding- try something completely different. Leos love waxworms. You can find them now in the northern states in bait shops, etc. Hold the waxworm and see if it take it. If it does not eat, put in 2 or 3 in the cage but take them out and throw them away the next day if the gecko doesn't eat. When you hand feed, watch for interest from the gecko. If it shows no interest, try the next day. If there is still no feeding occurring, you certainly have an issue with illness. In place of waxworms, try silkworms or any worm that crawls. The important action is to get the animal to eat.
5. Finally, last resort (and this all hinges on the non-availability of a vet- which really should be your first action), feeding manually. DO NOT DO THIS UNLESS THE ANIMAL IS NOT EATING AT ALL. Use an eyedropper and try to feed the gecko yourself. I've used baby food in the past with vitamin and mineral supplements added. I've heard some use pedialyte.
The important note here is that the leopard will be very hesitant to allow you to feed it. You MUST be very gentle and only put the eyedropper (or syringe made especially for lizard feeding) into the mouth as far as needed to 'drip' in food into the corner of the mouth. Feed only a couple of mouthfulls initially and again monitor the poop.
There are medications on the market that you could use to treat your gecko but, this step should be taken by a professional.
Good luck with your animal and please let us know how it is doing and if you have any more questions.
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