Stock and bond markets suffered on Wednesday after President Donald Trump's sweeping tariffs came into effect and China retaliated.

Even before President Trump's announcement that he plans a "major tariff" on pharmaceuticals, the sector was getting hammered in the markets — and not just over concerns about higher costs. Why it matters: Investors are also responding to broader uncertainty about the Food and Drug Administration and how the industry will be regulated,

Billionaire investors are in an unfamiliar position, watching and cringing as tariffs roll on and the stock market reels.