How to Switch from Percorten V to Florinef

It used to be that Percorten-V was the only medicine available to treat canine Addison’s disease. Then along came Florinef, which is a human treatment for Addison’s disease; it is used “off-label” to treat Addison’s in dogs. While prices for both medications can vary wildly, owners of toy dogs might find it cheaper to switch from Percorten V to Florinef. Percorten-V is only available in the U.S., Denmark, Canada and Australia.

Step 1: Start Florinef administration on the date of your dog’s next scheduled Percorten-v dose.
Step 2: Get electrolytes tested every one or two weeks to ensure that normal serum sodium and potassium levels are being maintained. As Florinef isn’t as effective in dogs as in humans, a wide range of dosages are required to control serum electrolyte concentrations. The usual starting dose is 0.01 mg/day/lb, but your dog may end up needing a lot more — or a lot less.
Step 3: Adjust the dosage if necessary to maintain serum electrolyte concentrations.
Step 4: Continue to administer Florinef once a day.

Tip: Monitor your dog regularly for electrolyte levels. Some dogs may become resistant to the drug.
Warning: Watch out for side effects. Florinef can cause polyuria, polydipsia, incontinence, mild hyperkalemia and hyponatremia

Reference: Essentials of Small Animal Internal Medicine [Richard W. Nelson, C. Guillermo Couto]