Some 9,000 Hawai'i teachers will see their medical expenses double starting Wednesday due to a cut in their medical benefits.

The insurance claims of Hawai'i State Teachers Association members will no longer be processed through the state's largest health insurance provider and claims administrator, the Hawaii Medical Service Association.

Many teachers aren't happy about the move.

The self-funded medical plan of the HSTA has covered 90 percent of health care costs. Members will be switched to a new plan offering 80 percent payment, administered by HMA Inc., an Arizona-based company.

Switching administrators and cutting benefits was necessary to keep costs in check, said Rod Shinno, administrator of the HSTA's Voluntary Employees Beneficiary Association Trust, which provides medical insurance to its members but farms out the administration to a third party.

"In order to keep the employee contribution level the same as it is now, we needed to take both steps," Shinno said.

Employees will pay 20 percent of health care costs, rather than 10 percent under the old plan. The new plan also has a maximum lifetime payout of $1 million, compared with $2 million under the old plan. The annual copayment maximum — the total out-of-pocket expenses before the insurance pays 100 percent of the cost — has risen to $7,500 from $6,000 for a family.

Members will have to choose their health care providers from a list created by HMA. But that means teachers will have fewer choices, said Larry Denis, a first-grade teacher at Kapi'olani Elementary School.

"A lot of Hilo providers aren't participating with HMA, so HMA wants us — the members — to nominate providers," Denis said. "They're making us do their work."

Now that doctors and pharmacies have learned about the switch, more are signing up to be HMA providers, Shinno said.

Other health plans offered by HSTA — such as Kaiser, HDS Dental, VSP Vision and life insurance — are not affected by the change.