Safety of oral and intravenous mycophenolate mofetil in healthy cats.

Objectives The aim of this study was to evaluate the safety and clinical effects of intravenous (IV) and oral mycophenolate mofetil (MMF) in healthy cats. Methods A total of 24 healthy adult cats weighing >3.5 kg were either given IV MMF (over a 2 h infusion) or oral MMF. The dosages used were as follows: 5 mg/kg IV once (n = 2), 10 mg/kg q12h IV for 1 day (n = 1), 20 mg/kg q12h IV for 1 day (n = 6) and 10 mg/kg q12h IV for 3 days (n = 5). Blood was collected from each cat at intervals of up to 12 h from the last dose for analysis purposes. Oral MMF was given at 10 mg/kg q12h for 7 days (n = 3), 15 mg/kg q12h for 7 days (n = 3) and 15 mg/kg q8h for 7 days (n = 4). Results Side effects to MMF were minimal. There was no anorexia or vomiting noted in any of the cats during or after IV medication administration. Only 4/14 cats had diarrhea from 12-48 h after IV administration. There was hyporexia in 1/10 cats given oral MMF and no vomiting noted. In 5/10 cats given oral MMF, there was diarrhea between days 2 and 7 of the study. Conclusions and relevance Cats tolerate MMF at an IV dose of 10 mg/kg q12h for 3 days and an oral dose ⩽15 mg/kg q12h for up to 7 days. There seems to be a dose-dependent incidence of gastrointestinal side effects. MMF may be a useful alternative immunosuppressant to be considered for use in some cats.