AlteredMind is right, loss of appetite is a symptom of some underlying problem and it will take some detective work to figure out what that might be.
Temps and lighting are the obvious places to start. How long have you hade your beardie? Has everything up to now seemed normal? What and how much has it eaten up to this point? Is it still active at all? Did you aquire it from a private source or from a pet store?
My next guess would be parasites. Have a fecal done immediately. Any veterinary clinic can do this. Drop some fresh poop in a baggie, date and name label it and drop it off the same day. If you can't get it there the same day, put it in the fridge overnight (and tell them it was refrigerated and for how long). Any anti-parasite treatment should be accompanied by excellent housing maintenance (Remove all waste immediately. Aquire some novalsan and clean everything daily.) and supportive care. **Make sure your dragon stays hydrated.** The pedialyte/babyfood/vitamin mix is good. A pedialyte/mushed high quality pellet mix would be even better if you can get your hands on pellets. Make sure your dragon is drinking and/or soaking daily. Keep it warm while it soaks. Isolate it from any other household members (of all species) and reduce handling to the minimum required for feeding and maintenance. If you can order some Parazap it makes excellent support for the treatment of parasites and stimulates the appetite.
There is also the possibility of a viral or bacterial infection and for this you will need a good vet, excellent supportive care during treatment and sadly, to be aware that not all infections of this nature are curable
. Hopefully, things will not be that bad.
Finally, if you find the cause is parasitic or infectious in origin, you owe it to other animals and keepers to notify the place where you aquired your beardie.
Keep us posted and good luck!
Best,
michele
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