my leopard gecko wont eat.

Question
hello, ive had my leopard gecko for almost a year now and he is just over 5 years old. about 4 months ago he stopped eating as much as he used to, and we thought that it could be because he was lonely as he had been alone his whole life, so i put my female leopard gecko with him (who is the same size but three years younger). he still isn't eating, and is now VERY skinny, his bones are sticking out. his surroundings haven't been changed and neither has his diet. he is kept on calcium sand and the temperatures are around 75-80 in the warm side of the viv and around 70 in the cooler side. i am really worried about him and would like some advice?
thanks.

Answer
Hi Sophie, There are a couple things you mentioned that I would suggest you change. It does however sound like your gecko has reached a state of extreme emaciation so I really can't suggest that these changes will cause a dramatic turn-around in his condition, a vet visit is really your best option.
Your warm side temperature is a bit low. Leopards should have a hot spot up in the 85 - 90 F range. Inadequate temperature affects all their metabolic processes including digestion and their immune system.
The other potential problem is the calcium sand. I was working in the reptile retail trade when this product first came out and it sounded great and we started stocking it. After several months on the market the necropsy (autopsy) results on reptiles started hitting the on-line forums and the magazines. Those calcium based sands were not dissolving in the stomach as claimed but were clumping instead and actually causing intestinal impactions. To make things worse, many owners thought their animals were attracted to it and purposely consuming it because of the colours and being calcium based. We could no longer recommend it and took it off the shelves.
Try to keep him hydrated by soaking or dripping water over his snout. You can also boost his nutrition by dabbing some chicken based baby food on his snout. They usually respond by licking it off. If you do suspect that he is impacted it wouldn't hurt to add a couple drops of mineral oil (any drug store carries this) to the baby food.