All the other comments here seem to be speaking strictly of illegal drugs that otherwise can't be obtained. There is also a market for things like semaglutide,

All the other comments here seem to be speaking strictly of illegal drugs that otherwise can't be obtained. There is also a market for things like semaglutide, HGH, any sort of anabolic steroid, ED drugs, certain types of stimulants and asthma meds, that are fairly trivial for any American to get a prescription for from an online clinic in the next half hour if they want, but they'll be charged extortionary prices. You can also buy these same things for 1/100th the price from well-established, well-known black market labs that will reimburse you for third-party blind purity testing, and nobody is ever going to arrest you for it, public ledger or not. Or take your chances handing over cash to some dude in an alley.