Going off food isnt always a cause for alarm, especially this time of year - but that coupled with weight loss and lethargy - something is definately up!
Could you give some more details?
- How old is the Leo in question?
- What size tank is she in?
- Is she housed alone or with other leos?
- What substrate is she on?
- What are the temps on the floor of the warm side?
- What type of thermometer are you using?
- How is the tank heated?
- How many hides does she have?
- When she is eating, what do you usually feed, and what kind/how often do you supplement?
Problems with husbandry such as inadequate temperatures or excessive stress can lead to inappetance. Parasites can also be a cause of not wanting to eat. So can impaction. There are lots of possible causes. Whenever a Leo stops eating the first thing is to double check all husbandry - temps on the floor of the warm side should be 88-92, these should be measured digitally. If anything is amiss with the husbandry, that should be corrected to see if she improves.
However, with this Leo since she is acting lethargic and is losing a lot of weight, i think you should start supplemental care, as well as checking husbandry. How thin is the Leo now? Do you have a gram scale you could use to weigh her? Could you post a picture of her?
I would soak her daily in warm water, shallow water - especially since she is weak. Stay with her to ensure she doesnt drown. This will help her rehydrate.
You can also make up a slurry using the recipe from Marcia at Golden Gate Geckos - which i have included below. This can be dribbled onto the lips with a syringe - often times the Leos will lick it up and it helps provide some much needed nutrition.
Acidophiliz (available at reptilesupply.com) can also be used. Its a probiotic, a very safe product that helps replenish good gut bacteria - this good bacteria can be wiped out in times of stress, and this leaves the animals feeling very poorly. It comes in a flavored liquid that can be dripped onto the nose and licked off. Sometimes it helps them get some of their "pep" back.
All of the above suggestions are just supplemental care. Anorexia and lethargy are symptoms of another problem - for her to improve you need to identify the underlying cause. These measures are just to help her feel better in the meantime, and hopefully keep her going and get some of her strength back.
Any husbandry issues should be correct (the answers to the above questions are very important) and if all the husbandry is correct, or if she does not show improvement with the corrected husbandry and supplemental care - then she needs to see a good reptile vet. The condition you are describing - drastic weight loss, lethargy etc make me feel that the condition is quite an emergency...any husbandry problems should be corrected immediately, and a vet should be consulted if she doesnt start to show improvement shortly after this.
Hope this helps!!
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