The 2022 contrast dye shortage, when one Shanghai plant slowed CT scans nationwide

On April 19, 2022, a manufacturer whose iodinated contrast media were used by about half of US hospitals and imaging centers, by a later Senate estimate, wrote to its customers that it was limiting orders. A COVID-19 lockdown had shut its contrast plant in Shanghai, RSNA News reported¹. By May 13, FDA was reporting shortages of iohexol and iodixanol, agents used to make blood vessels and organs show up on CT scans, according to a Wisconsin insurance bulletin² issued that day.

At one academic medical center in Nashville, the radiology department counted what it had left and found 7 to 10 days' worth, according to its published account⁶.

Contrast media rarely come up in discussions of drug shortages, but they are injectable drugs, and the 2022 episode is one of the clearest recent cases of a single plant's shutdown reaching nearly every US hospital within weeks. FDA documents, a Senate letter, a state insurance bulletin and the studies hospitals published afterward show how it unfolded.

One plant and a city lockdown

According to RSNA News¹ on May 16, 2022, the affected supplier was one of four manufacturers of iodinated contrast and had told customers to expect an 80 percent reduction in supplies through the end of June. The Shanghai factory had reopened by then. A company update two days later put it at 50 percent capacity.

On June 30, two members of the Senate health committee wrote to FDA Commissioner Robert Califf. Their letter³ said the shortage "has impacted as many as half the nation's hospitals" and limited their ability to provide "the estimated 50 million scans performed with contrast media every year in the U.S." It put the affected company's share at about half of all US hospitals and imaging centers, said the products were "primarily produced" in Shanghai, and that the company had begun flying in shipments from Shanghai and from a plant in Cork, Ireland, that would normally travel by sea.

In the same letter, the senators recalled an exchange at an earlier hearing on the infant formula shortage. Asked what the next supply chain crisis would be, Califf had named contrast media, the senators wrote, calling the shortage "unbelievable…but it's happening."

Demand for these agents is large and spread across the hospital. Using 2019 Medicare claims, a Journal of the American College of Radiology analysis⁷ counted 29,327 contrast-enhanced CT services per 100,000 fee-for-service beneficiaries, led by the abdomen and pelvis (13,952) and the chest (9,685), with the emergency department second only to hospital outpatient departments.

What FDA did

FDA's first step was the listing itself, which put iohexol and iodixanol in the agency's shortage database. GxRadar explains how that database works in How FDA tracks drug shortages.

Its most visible step came in July. A July 6, 2022, letter to health care professionals⁴, posted on FDA's website, said that a second contrast manufacturer was "coordinating with the U.S. Food and Drug Administration" to import iomeprol, an intravascular iodinated contrast agent sold abroad that "FDA has not approved." The letter cited "critical shortages" of iohexol, iodixanol and iopromide. The imported product came from plants in Germany and Italy, and the letter's table of lots shows cartons labeled in French, English, Spanish and Russian. FDA's discretion, the letter said, was limited to that one company and to the period of the shortage.

That kind of shortage importation runs on FDA's enforcement discretion, separate from the state importation program described in Drug importation under section 804. FDA's report to Congress for 2022⁵ says the agency exercised "regulatory flexibility and discretion" in 87 instances that year, affecting 76 products. The report does not list them by name.

In their letter³, the senators asked whether FDA was working with other producers "to try and import and/or approve additional products," whether it was helping direct supply to the facilities that needed it most, and what it was doing to learn of supply problems earlier.

What rationing looked like

At least one state regulator stepped in. Wisconsin's insurance commissioner issued a bulletin on May 13² encouraging health plans to allow "increased flexibility around the use of contrast materials in CT scans," citing American College of Radiology advice that included alternative agents, non-contrast CT where appropriate and weight-based dosing.

Inside hospitals, the tactics were blunt. The Nashville center's report⁶ lists pharmacy splitting single bottles into smaller doses under sterile technique, reduced doses by exam type, non-contrast trauma scans for lower-risk injuries, and postponing cancer follow-up scans scheduled more than nine months after the previous one. Its command center cut contrast use by about 50 percent in less than seven days. RSNA News¹ reported in May that hospitals across the country were postponing treatment-monitoring scans for cancer patients.

Several studies have since measured what changed.

Sources: American Journal of Neuroradiology, 2023⁸; Pediatric Emergency Care, 2025⁹; Cureus, 2022¹⁰; Current Problems in Diagnostic Radiology, 2026¹¹.

Broken out by supplier, CT perfusion studies using the affected company's contrast fell 43.06 percent, while those using other companies' agents rose 2.93 percent, a difference that was not statistically significant, according to the paper⁸.

Once supply returned, repeat imaging and length of stay approached pre-shortage levels, but costs stayed higher in the short term, according to the 2026 cost study¹¹.

What the episode exposed

Contrast agents are sterile injectables, and the shortage followed the pattern GxRadar describes in Why sterile injectables dominate shortage lists: concentrated production, little spare capacity and long lead times to replace lost output. Here the concentration was geographic as well. One city's lockdown removed most of the supply for half the country's hospitals, a risk our explainer on where drug ingredients come from discusses for other drugs. Two years later a single damaged plant produced a similar squeeze in the 2024 IV fluid shortage.

Most of the fixes that followed were local. Radiologists quoted by RSNA News¹ pointed to contracts with more than one vendor, a choice that sits inside the purchasing system described in how hospitals buy drugs. The senators called for diversified supply chains and more competition. FDA's own toolbox was the one described in its annual report, case-by-case flexibility and temporary importation.

A GxRadar query of FDA's shortage data in November 2026 returned no current iohexol or iodixanol entries. Our shortage tracker shows what is listed now, and the supply chain desk follows single-source risks like this one.