Hundreds of senior citizens across the Islands have left briefings this week on the upcoming Medicare prescription drug benefit plan armed with new information and the task of figuring out whether it will work for them.

But they've also gotten the message that state and federal officials will help them untangle the complicated plan that goes into effect Jan. 1.

"You're not alone," Mary Rydell, Pacific area representative for the Centers for Medicare & Medicaid Services, told 175 senior citizens gathered at the Pacific Beach Hotel yesterday. "There is help to help you figure this out. Take your time and think about it because you have to decide what's best for you."

But they don't have a lot of time.

The enrollment period runs from Nov. 15 through May 15 and there are costly penalties for people who sign up after May.

And by mid-October, Rydell expects that senior citizens will be bombarded by solicitations from healthcare plans in Hawai'i and new ones from the Mainland trying to sign up clients for their individual programs, which will help defer the overall costs.

"People are going to be out there marketing the heck out of this thing because there's a lot of money to be had," Rydell said in an interview.

Senior citizens also should expect to receive information from their existing drug plans on whether the Medicare drug program is better or worse than what they currently receive, Rydell said.

"Don't throw anything away," Rydell said. "You really have to read your mail this fall."

She and Pamela Cunningham of the state Executive Office on Aging know that many state and county retirees, such as teachers and other members of public employee unions, are better off staying with their existing plans.

The new prescription drug plan represents what some people are calling the most significant change to Medicare in its 40-year history. In Hawai'i, 186,157 people are estimated to be eligible, with 134,774 on O'ahu.

The premium for the Medicare drug plan is estimated to cost anywhere from $27 to $32 each month. Senior citizens in the plan also will have to pay the first $250 of their drug costs each year — and 25 percent of their drug costs from $250 to $2,250.

For many senior citizens, the most difficult part will be figuring out whether their current — or future — drug costs will run from $2,250 to $5,100 per year. If their costs fall into what the AARP calls the "doughnut hole" of $2,250 to $5,100 per year, senior citizens in the program will have to pay 100 percent of their drug costs.

But if their costs are higher, Medicare will then pay 95 percent of their expenses after the senior citizen has paid $3,600 per year in out-of-pocket costs.

It's those kinds of calculations — and the forecasts of their future drug needs — that are confusing senior citizens across the country.

So this week, representatives from AARP Hawai'i, Medicare, the state health department and U.S. Sen. Dan Akaka's office set up seminars and information booths across Hawai'i.

They have tentative plans for future sessions, but none scheduled yet.

After attending yesterday's session at the Pacific Beach Hotel, Herbert Ishida, 74, a retired Hawaiian Airlines aircraft mechanic from Mililani, was certain that the new plan will benefit his wife, Lillian, 73, who takes several prescription drugs.

But Herbert still needs to figure out whether the monthly premiums of about $30 a month and other costs will benefit him since he doesn't take any medications.

At least not yet.

"It works for my wife," Ishida said. "But I have to make a decision."

Like Ishida, Roger Lum, 77, a retired engineer, looks at the new plan as insurance for any future drug needs he may have.

Lum's medical plan covers only hospitalization and basic care. He has no drug, vision or dental coverage since he retired.

"I pay for whatever drugs the doctor orders, which isn't much," Lum said. "But I know I'm going to need this some day because no one's taking care of me."

Reach Dan Nakaso at dnakaso@honoluluadvertiser.com.