The present invention relates to a method for treating patients exposed to chemical or biological weapons comprising administering a compound capable of depleting mast cells or a compound inhibiting mast cells degranulation, to a human in need of such treatment. Such compounds can be chosen from c-kit inhibitors and more particularly non-toxic, selective and potent c-kit inhibitors. Preferably, said inhibitor is unable to promote death of IL-3 dependent cells cultured in presence of IL-3.