Questcor and its controversial flagship drug Acthar have come under fire from short sellers. The drug's many grandfathered indications and high pricing have made it an easy target as bears wait for a cheap competitor or insurer pushback. But they forgot one thing -- unless or until that happens, Questcor is a moneymaking machine.

In this video, health-care analyst David Williamson dives in to Questcor's second-quarter results in greater detail, discusses how dangerous it is to short a stock like Questcor, and talks about why this stock still may not be a good fit for Foolish investors.

Follow David on Twitter: @MotleyDavid.