My sugar glider is only 1 year 7 months old. He has been on antibiotics for the last few days. When I took him to the vet he didn't see anything wrong with him other than he had lost A LOT of weight. He gave me antibiotics any way just in case. Well my sugar glider really picked up, he was almost back to normal and had put weight on again and was eating. He was perfectly fine and bright last night but this morning he had passed :(. I feel awful. Any idea what could've happened?

Really difficult to tell, the previous weight loss might have weakened his heart, or might have been caused by organ/ metabolic issues, or the 2 events could be totally unrelated.

What diet was he on, did the vet test for parasites?

Another question I would ask is what was the temperature in the room last night? I ask this because over here I saw several gliders their owners thought were dead but who were in fact in torpor state (usually induced by cold temperature, more likely to happen to lone gliders, even more glider with low weight since it's a way for the body to save energy, unfortunately it often proves fatal to weak gliders)

He has always been on the lighter side for a male sugar glider. He was fed on the SGS 2 diet. I think the vet checked, he looked in his fur and in his mouth.

It was about 18 degrees Celsius. Idk if it means anything but his hand was jammed in his mouth when I found him.

My experience with SGS2 is that it needs much more than the 1 TBS recommended per glider (mines are almost at 2 TBS per night). I personnally don't like the traffic light system which is based on ratios rather than on effective amount, by using only vegetables in the green and orange sections, you could still end up with a negative ratio on the total mix depending on the quantities of each. I also notice that they drink a lot more water with this diet than with all the others that I have tried.

18C is fine, so the problem was not temperature.

If the vet did not do fecal tests, it's really difficult to guess.

I couldn't tell you what happened, only that I'm so sorry for your loss.

The vet did say he wanted to do one but couldn't get any from my suggie.

Thank you both xx