The marketing of medicine in inherently unethical because it seeks to override doctors and consumers information-based evaluations, and instead make a choice based on emotional propaganda. The harm caused by any given medical advertisement is directly proportional to its effectiveness. Every pharmaceutical sales rep is an immoral cancer on our society.
To play Devil's Advocate - without pharmaceutical companies developing and marketing drugs, how do we set up an incentive structure that encourages R&D and innovation?
There is moral validity to profit-seeking investment in drug trials which find effective treatments, but the current system enables this only with great amounts of inefficiency.