San Francisco could become the first U.S. city to require all its pharmacies to always carry the opioid overdose antidote naloxone, according to The Associated Press.

A bill being introduced this week by San Francisco Supervisor Matt Dorsey would require every pharmacy to always have in stock at least two naloxone nasal sprays or face fines. The city has long struggled with large-scale fentanyl use and fatal overdoses.

Last year, more than 70% of the 647 accidental overdose deaths in the city were attributable to fentanyl. Preliminary report show an increase of more than 40% in overdose deaths in the first five months of 2023 compared with the same period in 2022. More than 79% of those deaths this year were attributable to fentanyl, according to the city medical examiner’s office.

A recent “secret shopper” survey conducted by the San Francisco Department of Public Health found that about 20% of San Francisco pharmacies did not have naloxone in stock, even though they had legal authorization to provide it upon request.