Hawaii is one of 23 states in the U.S. that reached a settlement barring a Japanese pharmaceutical company from anti-competitive conduct for 20 years.

The state attorney general’s office announced today that Teikoku Seiyaku Co. Ltd., the for-profit parent company of Teikoku Pharma USA, faces a 20-year injunction prohibiting it from paying or incentivizing a generic drug maker to delay entry into the drug market or from researching, developing, manufacturing, marketing or selling any drug product.

Teikoku was accused of illegal participation in an agreement to protect a monopoly on Lidoderm, the brand name for lidocaine patches widely prescribed for relief of pain associated with post-herpetic neuralgia, a common complication of shingles.

“Blocking generics means fewer choices and higher medical costs for Hawaii consumers who are suffering,” said state attorney general Douglas Chin in a press release. “This agreement provides a great mechanism for the States to enforce against bad companies trying to prevent competition.”