A new Medicare enrollment period, the Limited Open Enrollment Period, begins Sunday and could cause confusion for some Medicare beneficiaries. The period allows patients in traditional Medicare, which requires payment of premiums and a percentage of fees for health care needs, to sign up for Medicare Advantage plans, some of which lack drug coverage. Medicare Advantage plans are private health plans that provide physician services, hospital visits and other health benefits to Medicare beneficiaries and are subsidized by the federal government. Some insurers are offering lower premiums and co-pays as well as perks like eye exams, hearing aids and acupuncture treatments for these Advantage plans, giving seniors incentive to switch, according to a report in the Oakland (Calif.) Tribune. However, beneficiaries who lose drug coverage as a result of a choice made during the Limited Open Enrollment Period will not be able to get it back until 2008 and will have to pay a penalty each month on their Part D premiums for dropping the drug coverage. Open enrollment runs from April 1 to December.