I have an 11 year old Devon Rex cat who has been very healthy and active up until now. In the space of three hours she when from her usual to self to completely lethargic. She doesn't move except to maybe lift up head to look at me. She also threw up. There was nothing in her stomach as she did not eat supper so she just brought up her stomach juices. She walked to the litter box and went but apparently didn't have the energy to make it back to bed and just lay down on the carpet. She didn't come when I called either. It came on so quickly though. Any ideas as to what the problem may be? How worried should I be? I am now very worried.
If this condition continues through the day then I recommend a vet visit. vetcare