Six groups of 6 lambs were treated orally with rafoxanide [a fasciolicide and nematocide] at dosages ranging from 0-37.5 mg/kg live mass in multiples of 7.5 mg/kg. The lambs were slaughtered 27-31 days after treatment for post mortem examination. No clinical, ophthalmological or pathological changes attributable to treatment were detected in any lamb. Possible differential diagnoses and predisposing factors for rafoxanide toxicity were discussed. Plasma-rafoxanide assay can be used as a diagnostic tool.