The Effectiveness of Acriflavine and Ineffectiveness of Proflavine as Immunosuppressant Agents

Acriflavine hydrochloride N.F. is an immunosuppressant agent containing approximately 80% acriflavine and 20% proflavine. The structures of these two diaminoacridines differ only with respect to a methyl group at the 10-position of the acridine nucleus. Antibody production to BSA in rabbits was suppressed by acriflavine but not by comparable or higher doses of proflavine. The degree of immunosuppression was related to the amount and duration of acriflavine administration. One course of acriflavine treatment during the first exposure to BSA was sufficient to induce a degree of immune paralysis to a subsequent dose of BSA. Acriflavine administered via the oral route was absorbed poorly and resulted in a high mortality.