PHILADELPHIA — Lannett Co. has gained Food and Drug Administration approval for metaxalone tablets 800 mg, a muscle relaxant.

Lannett said Monday that its product is a generic version of Skelaxin tablets (800 mg) from King Pharmaceuticals Inc.

Metaxalone alleviates musculoskeletal pain by blocking nerve impulses in the brain.

“Metaxalone tablets, indicated as an adjunct to rest, physical therapy and other measures for the relief of discomforts associated with acute, painful musculoskeletal conditions, is the 10th product approval we have received in calendar 2016,” stated Arthur Bedrosian, chief executive officer of Lannett. “With only three current competitors, this approval represents a meaningful market opportunity. We anticipate launching our metaxalone product within this quarter.”

For the 12 months ended in September, metaxalone tablets (800 mg) had total U.S. sales of approximately $173 million (at average wholesaler price), according to IMS Health data reported by Lannett.