Excessive Thirst

• Prednisone often makes a cat feel thirsty, and it then drinks excessive water. The extra water makes the cat need to urinate more often.
  
  

Excessive Hunger

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  Prednisone is used to stimulate a poor appetite. The medication can make the cat crave food and may cause weight gain.
  
  

Upset stomach

• The stomach and digestive system of the cat can be upset by prednisone, causing the cat to have diarrhea.
  
  

Infections

• Prednisone, especially at higher doses, affects the immune system. Dormant viruses and infections can appear and require treatment.
  
  

Behavior

• Behavior changes such as sudden aggression or hiding can be triggered by prednisone.
  
  

Hair Loss

• Long-term prednisone use affects cat hair, causing it to become dull or fall out.