In the past few months, it's become nearly impossible to buy Ketaset in New York City's underground drug market. Made by Fort Dodge, an Iowa-based pharmaceutical firm, Ketaset is a brand of ketamine, a compound that blocks certain neuroreceptors, causing hallucinations in high doses and, in lower doses, a fuzzy dissociation--like the warmth of a couple of Jim Beams. Legally, it's used as an anesthetic. Illegally, one snorts ketamine because the fuzziness lasts half an hour and doesn't produce bourbon's four-Advil hangover.
Ketaset's scarcity dates back to August 1999, when the U.S. Drug Enforcement Administration, acting on preliminary evidence that ketamine...