CVS operates 9,700 pharmacies and 1,000 MinuteClinics. A decade ago, it also purchased Caremark and now operates CVS/Caremark, a pharmacy benefits manager (PBM), a type of business that administers drug-benefit programs for health plans. CVS/Caremark is one of the three largest PBMs in the United States. Along with ExpressScripts and OptumRXTogether, these three control at least 80 percent of the market.

Should U.S. consumers be happy or concerned about the pharmacy’s proposed merger with Aetna health insurance? As a professor of health law and bioethics, I see compelling arguments on both sides.

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