WASHINGTON, D.C. ? When people enroll in a Medicare drug plan later this year, the first option for paying their monthly premiums will no longer be through a deduction in their Social Security check. Instead, the government will encourage beneficiaries to pay insurers directly.

The change should reduce the number of errors that have plagued the drug benefit since it kicked in Jan. 1. The most recent glitch was the mistaken reimbursement of monthly premiums to an estimated 230,000 Medicare beneficiaries.

Under the drug benefit, some 23 million beneficiaries are enrolled in private plans. Most pay a monthly premium, and many of those who pay such a premium are running into problems.

Some beneficiaries have had too much money withheld. Others have had premiums withheld, but the government never forwarded the money to the insurers. In other cases, low-income beneficiaries eligible for extra help with their premium have not been credited for the subsidy. Instead, the Social Security Administration has been withdrawing the entire monthly premium from their check.