"Those who dislike the practice, according to ProCon.org, might argue that the money spent on advertising is passed on to consumers. Ads cause people to pick medicines based on the effectiveness of the ad rather than the effectiveness of the medication, and ads cause patients to desire and request medications from their doctors that may be unnecessary, thus leading to an over-medicated and unhealthy society. Those in favor of these ads argue that consumers should be informed about medical conditions and therapies, and the ads even help to de-stigmatize certain conditions. The ads might even be said to help demystify medical treatment and doctors themselves, who should not be seen in such a powerful, almost godly light."
The argument that some people will pick medicines based on the effectivness of the ad not the medication is valid. But I will agree that the ads might help de-stigmatize certain medical conditions. Who remembers being embarrassed in elementary school when your mother would write a note that said you had 'diarrhea' and had to stay home? Now we can blog about cancer and not piss off most normal people (a note to the British blogger).
Lets just say they spend $5 billion (with a b, not an m) in direct to consumer advertising each year. What if they applied that tiny chunk of change to lowering their prices? They also spend another $20 billion promoting their products in other ways - this would be maybe (and I am speculating here) conferences, speaker fees, packaging, market research, and more.That $20 billion could also help reduce medication costs.
This is all my opinion but I don't think those ads have ever helped much - just confuse everyone with their side effect lists. And allow the creative ones among us to create endless spoofs. If they are becoming a joke in popular culture, that might give you an idea of how well the ads really work.