After three years on the tube, skating icon Dorothy Hamill may need to hunt for yet a third career. In part that's because the Olympic gold medalist returned to the spotlight as a television pitchwoman for Vioxx, the blockbuster painkiller Merck ( MRK) yanked off the market last fall. But another factor is that Hamill's ads exemplify a type of advertising that some people would like to see banned altogether -- so-called direct-to-consumer prescription drug advertising. Indeed, Hamill's own commercials -- which helped make Vioxx a household name -- could very well fuel the crusade against DTC spots. Ads for Pfizer's ( PFE) Celebrex, a drug similar to Vioxx, have already been pulled from the market. Both of the heavily marketed painkillers, known as Cox-2 inhibitors, have been linked to heart attacks. Some high-profile medical experts were calling for a crackdown on DTC drug advertising even before the Vioxx recall. They insisted that the ads, supposedly designed to "educate" the public, actually did more harm than good. Now, their warnings are starting to sound more prescient than ever. "When one considers that the majority of DTC drug ads are now on television -- and that this means a hasty 30- or 60-second spot -- it is hard to imagine that much more than the name and the claimed therapeutic indication could ever be conveyed," Arnold Relman, the retired editor-in-chief of the New England Journal of Medicine, testified in July 2003 before the U.S. Senate Special Committee on Aging. "There simply isn't time to provide any useful information about side effects or complications." In this third of five articles probing Merck's troubles in the wake of the Vioxx scandal, TheStreet.com examines how a tectonic shift in the drug industry's advertising practices -- along with a hands-off stance by regulators -- set the scene for a disaster that has proved hazardous to consumers and Merck investors alike.