Side effects of shoulder steroid injections can range from common to rare. 
 
  • Common side effects:
    • Pain, swelling, or bruising at the injection site 
       
    • Redness or flushing of the face 
       
    • Temporary increase in blood sugar or blood pressure 
       
    • Insomnia or difficulty sleeping 
       
    • Increased appetite 
       
    • Thinning or discoloration of the skin around the injection site 
       
  • More serious side effects:
    • Infection in the joint or surrounding tissues 
       
    • Damage to the joint or tendons 
       
    • Mood swings, depression, or anxiety 
       
    • Hallucinations 
       
    • Fever or other symptoms of infection 
       
    • Excessive sleepiness or confusion 
       
    • Rapid breathing 
       
    • Puffy face and/or unexplained weight gain 
       
    • Soft-tissue calcification 
       
  • Rare side effects:
    • Septic arthritis, a life-threatening infection in the joint fluid