In accordance with the present invention, there are provided methods for the in vivo reduction of free radical levels in mammalian subjects in need thereof. In contrast to the inhibitory approach described in the prior art (i.e., wherein the function of the species responsible for free radical production is inhibited), the present invention employs a scavenging approach whereby overproduced free radical is bound in vivo to a suitable free radical scavenger. An exemplary free radical scavenger contemplated for use in the practice of the present invention is a dithiocarbamate-ferrous iron complex. This complex binds to free radicals, forming a stable, water-soluble free radical-containing complex. When administered to a subject afflicted with a disorder associated with free radical overproduction, the water-soluble free radical-containing complex is produced and then filtered through the kidneys, concentrated in the urine, and eventually excreted by the subject, thereby reducing in vivo free radical levels.