San Francisco ? Nineteen California pharmacies filed a state lawsuit Thursday accusing the world’s largest pharmaceutical companies of conspiring to inflate U.S. drug prices.

The pharmacies accuse the 15 drug makers of illegally conspiring to charge inflated prices in the United States while barring pharmacies from buying the makers’ drugs at lower prices outside the country.

“We are being charged higher prices than foreigners are being charged,” said Joseph Alioto, representing the pharmacies. “If we are selling the same drug we want to pay the same prices as everyone else.”

The lawsuit, filed in Alameda County court in Oakland, alleges the pharmaceutical companies have hurt the pharmacies’ bottom lines by violating California’s antitrust and unfair business practices laws.

The lawsuit comes at a time when pharmaceutical companies are under increased scrutiny over drug costs and their marketing practices. Many of the same drugs sold in the United States are available in Canada and elsewhere for fractions of the U.S. retail prices.