A temperature above 104 degrees Fahrenheit
If you have thermometer at home, you can check your pet's temperature if he just seems off. If you don't, again, common sense is key - if your pet feels unusually hot to the touch (especially after being outside in the heat, or along with other symptoms like vomiting or lethargy), get her checked out. Remember, however, that pets' temperatures are normally higher than people's, and don't panic unnecessarily - up to 102.5 degrees can be normal for a dog.