Information for US travelers returning from Italy, updated December 3, 2021, from the US Embassy in Italy:
** Effective December 6, 2021, all air passengers 2 years or older (citizens of all nationalities, including U.S. citizens, whether vaccinated or unvaccinated) with a flight departing to the US from a foreign country, are required show a negative COVID-19 viral test result taken no more than 1 day before travel, or documentation of having recovered from COVID-19 in the past 90 days, before they board their flight. Air passengers will also be required to confirm in the form of an attestation that the information they present is true. Please visit the CDC webpages for more information on the requirement for proof of negative COVID-19 test or recovery from COVID-19 for all air passengers arriving in the United States.
If you need help locating a pharmacy for a Covid rapid test prior to returning to the US, the website Farmacie di Turno has a search engine here that will tell you which pharmacies are open and offer rapid tests (tampone rapido).
In the search tool, where it says Città o CAP, type the name of the city or, if you know the postal code (CAP) of the place you're staying, you can type that.
Where it says "giorno" select the day, and where it says "ora" choose the time.
Click the button "avvia la ricerca" and it will show you the pharmacies that are open and their hours.
It's best to book in advance. It's a good idea to locate a pharmacy that's open for the day the test is needed and then go there in person or call ahead a day or two in advance to book an appointment.
For travelers departing from Rome, there is also a rapid test service at Fiumicino airport.