hairless rat

Question
my daughter's female hairless rat is 8 months old. today she came home and took the rat outside for about 3 hours. tonight the rat's tongue is all swollen and it looks to have lost weight. what can i do to help?

Answer
See a vet at once.  She may have eaten something from outside or is having an reaction to an insect bite.

Please tell your daughter it is not safe to have pet rat outside.  

Not only can they get into trouble by getting loose and running away and escaping into tiny holes that you cannot get them out of, but big large birds have actually came out of nowhere and would literally swoop down and grab the rat from the ground, right in front of the horrified rat owner and carry the rat off.   This is a real serious threat to rats and no pet rat should be allowed outside un-caged no matter what.