1. A drug tracking system comprising: a plurality of drugs; a plurality of drug tags, wherein each of the plurality of drug tags comprises a plurality of food dyes; wherein each of the plurality of drugs is associated with one of the plurality of drug tags when the plurality of drugs and the plurality of drug tags are combined with one another; wherein each of the plurality of drug tags produces a spectral signature detectable by either photographic or absorption spectroscopic analysis; wherein the spectral signature produced by each of the plurality of drug tags is distinguishable from others within the plurality of drug tags; wherein at least one of the plurality of food dyes within each of the plurality of drug tags identifies a member of a class within which at least one of the plurality of drugs belongs; wherein at least one other of the plurality of food dyes within each of the plurality of drug tags identifies specifically what at least one of the plurality of drugs is; and wherein the spectral signature is detectable in bodily waste.