Types

• The most common reactions to cyclosporine are loss of appetite, diarrhea and nausea. Other side effects include increased thickness of the coat, excessive shedding, foot calluses, ear redness or swelling, and swelling of the gums, all of which end once treatment is complete.
  
  

Time Frame

• Adverse reactions from cyclosporine are most likely to develop with the start of treatment. Often, side effects diminish as dogs continue to take the medication.
  
  

Drug Interactions

• Certain medications can increase the amount of cyclosporine in a dog's body, which increases the risk for reactions. These include the heart drug amiodarone, testosterone supplements, antifungal medications like ketoconazole, hypertension medications like amlodipine, the antibiotics imipenem and erythromycin, and the nausea drug metoclopramide.
  
  

Risks

• Infrequently, dogs treated with cyclosporine develop severe allergic reactions that cause facial swelling, hives, scratching, seizures, pale gums or cold limbs. These reactions are life-threatening and can result in shock, coma or death.
  
  

Considerations

• Veterinarians do not prescribe cyclosporine for pregnant or nursing dogs. And it may not be safe for animals with a history of liver dysfunction or any type of cancer to take the drug.