San Mateo County (Map, News) - The swelling costs of prescription drugs could be soothed by a hefty discount for tens of thousands of uninsured and underinsured San Mateo County residents.

A new proposal would cut the cost of prescription drugs by 22 percent at a time when approximately 80,000 of San Mateo County’s residents are uninsured, according to the county’s Blue-Ribbon Task Force.

But the best part, county Supervisor Rose Jacobs Gibson said, is that the program comes at no expense to taxpayers.

The Prescription Drug Discount Card program, available to interested county residents, would give the discount off any pharmaceuticals that aren’t covered by a resident’s insurance. About 77 pharmacies in the county have agreed to participate in the program, including Walgreens, Longs Drugs and many independent pharmacies.

The discount program is run by the National Association of Counties and was established in 2005. Since then, 983 counties nationwide have participated, including 10 in California. The only other county in the Bay Area already participating is Marin County, Gibson said.

The county’s Housing, Health and Human Services Committee recently recommended that supervisors adopt the free program. The county Board of Supervisors could review and possibly vote on the proposal as early as the end of this month.

Gibson, who introduced the national program to the county, said that the uninsured are not the only residents who stand to benefit from the program. Many insurance plans do not cover all drugs, and any drugs that are not covered by insurance can receive the discount.

For example, the most commonly prescribed drug for asthma is Advair, which is not covered by many insurance policies and costs about $177 a month, Gibson aide Michael Costa said; with the discount, residents could save about $35 a month, or about $420 a year, he said.

In a report by AARP, prices for nearly 200 of the most commonly used brand-name medications for adults rose, on average, 6.3 percent in 2006.

If supervisors adopt the program, they would begin negotiating a contract with the National Association of Counties, which in turn contracts with Caremark Rx Inc.

The program would not cost the county or taxpayers because Caremark negotiates the discounts with participating pharmacies, who in turn receive an assumed increase in foot traffic in their drugstores. Caremark would receive a small commission for every discount given.

“Prescription costs have skyrocketed, so it’s very difficult for people on a fixed income to afford the medications they need to take,” Gibson said. “This will be of tremendous benefit to San Mateo County.”

kworth@examiner.com