The share of workers compensation medical costs attributed to prescription drugs is leveling off, at least temporarily, according to a study released Wednesday by Boca Raton, Fla.-based NCCI Holdings Inc.

Several events could be playing a role, according to "Workers Compensation Prescription Drug Study--2007 Update." Those events include withdrawal of some drugs that were often prescribed in workers comp cases. The arm of the National Council on Compensation Insurance Inc. did not specify which drugs have been taken off the market.

Newly approved generic versions of popular drugs as well as a slowdown in the introduction of new drugs also could be contributing to the slowdown in pharmaceutical costs, the NCCI said.

Even though the growth rate of costs for prescription drugs has slowed, workers comp medical expenditures continue to rise and prescription spending is growing at least as rapidly as overall medical costs, the NCCI said.

More findings are available at www.ncci.com.