Peripheral neutrophil inclusions in amiodarone treated patients.

In 14 patients receiving chronic amiodarone therapy the appearance of multilamellar inclusion bodies in peripheral blood neutrophils was related to both plasma concentrations of amiodarone and its desethyl metabolite and unwanted effects of the drug. Seven of the patients had well defined inclusion bodies. In this group mean amiodarone and desethylamiodarone concentrations were significantly higher than in the remaining seven patients and all but one had unwanted effects of the drug. Of the seven patients without inclusion bodies only one, with high plasma amiodarone and desethylamiodarone concentrations, had unwanted effects of the drug. It is concluded that the appearance of multilamellar bodies in the blood neutrophils of amiodarone-treated patients may help to distinguish those patients at risk of long-term amiodarone toxicity.