Shoshana Speiser (J.D. 2011, Boston University) & Kevin Outterson (Boston University), Deductions for Drug Ads? The Constitution Does Not Require Congress to Subsidize Direct-to-Consumer Prescription Drug Advertisements, 52 Santa Clara L. Rev. 453 (2012):

The First Amendment protects lawful, non-misleading advertising as commercial speech, which constrains Congressional attempts to regulate direct-to-consumer advertising (DTCA) of prescription drugs. But the Constitution does not require the federal government to subsidize advertising through the Tax Code. Congress could revoke the legislative gift of tax deductions for DTCA without running afoul of regulating speech. While DTCA proponents maintain that DTCA increases disease awareness and leads to more doctor-patient conversations, Congress could find that these purported benefits are outweighed by other negative consequences, including excessive prescribing.