According to most veterinary formularies and references, the most common Nystatin dose is 200,000 to 300,000 IU/kg two or three times a day. Lafeber vet recommends 300,000 IU 2-3 times a day, so that is what I will base my calculations on.
Nystatin can be used to treat some strains of candida in poultry.
Medistatin contains Nystatin 400,000 IU per gram and comes in comes with a teaspoon sized scoop that when level contains ~3 grams, so one level teaspoon is 12,000,000 IU.
Your average sized chicken hen weighs about 5 pounds, so a hen this size will need 681,818 IU 2-3 times a day, which is ~0.6 teaspoons or 1.7 grams 2-3 times a day.
The per pound amount is 0.11 teaspoons per pound or 0.34 grams per pound three times a day.
Medistatin is sold *without* a prescription on most pigeon supply websites worldwide.
Lafeber Vet says: