Merck (MRK) shares plummeted 5.02% in intraday trading on Tuesday, as pharmaceutical stocks faced a double whammy of negative news. The steep decline came amid renewed concerns over President Donald Trump's impending pharmaceutical tariffs and the FDA's announcement of increased surprise inspections at overseas manufacturing sites.

President Trump stated on Monday that he would announce pharmaceutical tariffs within the next two weeks, reigniting fears of trade tensions in the sector. This announcement, coupled with Trump's hints at upcoming measures to reduce drug costs for consumers, has put significant pressure on drugmakers' stocks. The uncertainty surrounding the potential impact of these tariffs on global supply chains and drug prices has left investors wary.

Adding to the sector's woes, the U.S. Food and Drug Administration (FDA) revealed plans to expand its use of surprise inspections at foreign facilities that manufacture medicines for U.S. consumers. This move, aimed at ensuring foreign manufacturers face the same level of scrutiny as domestic ones, has raised concerns about potential disruptions in the pharmaceutical supply chain and increased compliance costs for companies like Merck with significant overseas operations.

The broader market also saw declines, with the Dow Jones Industrial Average falling over 300 points, further contributing to the negative sentiment surrounding pharmaceutical stocks. Analysts suggest that these developments could have far-reaching implications for the industry, potentially affecting drug pricing, manufacturing practices, and international trade relationships in the pharmaceutical sector.