A major area of potential abuse: It’s a magic piece of paper—the label—that is the cause.
"when 1) the intended use [of the drug] is unapproved and for a serious condition for which effective treatment may not be available domestically either through commercial or clinical means;
2) there is no known commercialization or promotion to persons residing in the U.S. by those involved in the distribution of the product at issue;
3) the product is considered not to represent an unreasonable risk; and
4) the individual seeking to import the product affirms in writing that it is for the patient's own use (generally not more than 3 month supply) and provides the name and address of the doctor licensed in the U.S. responsible for his or her treatment with the product or provides evidence that the product is for the continuation of a treatment begun in a foreign country/area." (Emphasis added)”