No one knows for sure the precise answer to the question asked in this post’s title, but we do know for sure that it’s significantly less than the 80 percent figure that is now bandied about as ‘fact.’
Reason‘s Eric Boehm deserves a Pulitzer Prize for his splendid investigative work into the 80-percent claim . That claim, again, isn’t close to being true. But what is true is the toxicity of the mix of carelessness and opportunism that lead people with political agendas to fabricate myths and spread them – and to entice unsuspecting others to swallow these myths whole.
Boehm’s piece is long, but it is well worth a careful read. Here’s just a slice:
Tracing this “80 percent of American drugs come from China” claim back to its source reveals a game of “whisper down the lane,” in which a rather innocuous piece of data about the global manufacturing base for pharmaceutical drugs has been inaccurately summarized and stripped of important context.
In December, when the U.S. and China signed the “phase one” trade deal—and when the coronavirus outbreak was still very much in the background—Politico published a story  (with some reporting from the South China Morning Post) framed around the idea that “U.S. policymakers” were worried that China could “weaponize” its drug exports to gain leverage in a trade dispute.
The piece was designed to scare. “The U.S. relies on imported medicines from China in a big way,” authors Doug Palmer and Finbarr Bermingham wrote right at the top. “Antibiotics, over-the-counter pain meds and the stuff that stops itching and swelling—a lot of it is imported from China.”
How much is a lot? “In all, 80 percent of the U.S. supply of antibiotics are made in China ,” they wrote, linking back to a press release from Sen. Chuck Grassley (R–Iowa).
But that’s not what the press release says.
Grassley’s statement was publicizing a letter  Grassley sent on August 9 to the Department of Health and Human Services (HHS) and the FDA, asking them to conduct more inspections of foreign drug manufacturing facilities to make sure they meet American standards.
“Unbeknownst to many consumers … 80 percent of Active Pharmaceutical Ingredients are produced abroad, the majority in China and India,” Grassley wrote.
There’s the first bit of context collapse: the authors of the Politico piece merged Grassley’s “80 percent … are produced abroad” into “80 percent…are made in China.”
All of this also raises another question: Where is Grassley getting that information? His letter sources that claim to a 2016 Government Accountability Office report  which itself cited FDA data on pharmaceutical manufacturers around the world. And that report makes it clear that the U.S. has a diverse supply chain for drugs that goes well beyond India and China.
“Nearly 40 percent of finished drugs and approximately 80 percent of active pharmaceutical ingredients (API) are manufactured in registered establishments in more than 150 countries,” is how the GAO summed up America’s pharmaceutical supply chain.
In two jumps, we’ve gone from “80 percent of American drugs are manufactured in more than 150 countries around the world” to “80 percent of drugs come from two countries” to “80 percent of drugs come from China.”