On September 9, 2025, the U.S. Food and Drug Administration (“FDA”) Office of Prescription Drug Promotion (“OPDP”) issued a torrent of untitled letters, 40 in total, just days after rumblings that FDA would be cracking down on direct to consumer (“DTC”) advertising of pharmaceuticals.[1] This enforcement flurry—which we will digest in a later blog post, given its complexity—did not stop there as just a week later, on September 16, 2025, FDA released about 80 warning letters. We have forecasted this for months, and now, we believe this wave of action to be the tip of the enforcement iceberg.[2]