Average pharmacy spend per injured worker increased 6.5% in 2009, according to a report on “in-network” transactions released Wednesday by a workers compensation pharmacy benefits manager.

The increase was driven by a 4.7% rise in prescription prices and a 1.7% uptick in utilization, according to Tampa, Fla.-based PMSI.

PMSI said its findings are based on a review of 5 million customer retail and mail-order transactions conducted from 2007 to 2009. The report excluded data for out-of-network pharmacy transactions.

PMSI’s “2010 Annual Drug Trends Report” is available online at www.pmsionline.com/annual-drug-trends-report.