Chronic drug shortages that threaten patient care are caused by rock-bottom prices for older generic medicines and a health care marketplace that doesn’t run on the rules of supply and demand, among other factors, according to a federal report published on Tuesday.

The report, the work of a task force led by the Food and Drug Administration and comprising representatives from various federal agencies, recommended that buyers like hospitals consider paying higher prices for older generic drugs.

Paying more would encourage drug companies to prioritize drugs like vincristine, a critical cancer medicine for children that now sells for just $8 a vial. To the consternation of cancer specialists, supplies of the drug recently have been scarce.

Cancer drugs are not the only medications in short supply. At any given time in the United States, there are shortages of well over 100 drugs, including many used for anesthesia, palliative care and septic shock, as well as vaccines and medical supplies like sterile water.