Salt is one of the most commonly used drugs in aquaculture. In fact, it is sometimes referred to as the aspirin of aquaculture. Salt, or sodium chloride (NaCl) in its chemical form, is a drug of low regulatory priority for the United States Food & Drug Administration and requires no withdraw-d time before marketing. Many forms of salt are used, including table, meat-curing, pickling, and rock salt. Of these, the most commonly used and least expensive form is the meat-curing variety. When used properly, salt can treat many external parasites including Costia, Epistylis, Trichodina, Chilodonella, and the flukes Dactylogyrus and Gyrodactylus. Salt is used to relieve stress during handling and transport.