Less serious side effects include: 1  Loss of appetite. 2  Weight loss. 3  Nausea. 4  Vomiting. 5  Diarrhea. 6  Frequent urination. 7  Muscle cramps, painful and swollen joints. 8  Excessive tiredness. 9  Difficulty falling asleep. 10  Headache, nervousness, dizziness. 11  Depression, mood swings. 12  Vivid dreams.
Nausea can occur in dogs for many reasons, particularly when the digestive tract and nervous systems are out of balance. Stress can certainly play a role in nausea.
Since Rimadyl chewable tablets taste like liver, they should be kept out of reach of your dog. Symptoms that your dog is suffering from a Rimadyl overdose include nausea, vomiting, stomach pain, headache, drowsiness, seizure, panting, slowed breathing or difficulty urination.