Doctors at several hospitals have been using a combination of midazolam, hydromorphone and ketamine. Under normal circumstances, they would use propofol and fentanyl because they are short-acting, the doctor said. The others have a longer duration and that makes it harder for patients to emerge from sedation later.

And with the peak in cases and resource use still projected to be several weeks away, the run on these drugs only highlights weaknesses in the current supply chain.

“The pharmaceutical supply chain is one of just-in-time production,” Ms. Fox said. “Manufacturers tend to make just enough product, and they forecast out their manufacturing cycles based on how much they sold in the past. Nobody expects to sell, you know, 10 times the amount of something, and so nobody has that on hand.”

Even before this crisis emerged, the Food and Drug Administration noted shortages of well over 100 drugs in the United States. And factory shutdowns in China, India and other countries may have exacerbated the shortage of some ingredients and generic drugs during the pandemic.

“Out of 21 antibiotics that would be critical for treating secondary infections in Covid-19 patients, 18 antibiotics have greater than 80 percent of their supply coming out of either China, India or Italy — all places that have had production disruptions,” said Stephen Schondelmeyer, a professor at the University of Minnesota’s College of Pharmacy who is a co-leader of the Resilient Drug Supply Project, which aims to provide a detailed map of the supply chain for important drugs used in the United States.

Another factor that can affect the global supply chain is when countries ban export of certain drugs, either because of trade wars or because they want to ensure supply for their own citizens, Mr. Schondelmeyer said. India, for example, has put a ban on the exports of 26 drugs and drug ingredients, including hydroxychloroquine, an old malaria drug that is being used around the world as a potential treatment.