Medicare Part D is an addition to Medicare Part A and Medicare Part B. Medicare Part D helps to cover prescription drug costs. Whereas Medicare Part A covers only hospital expenses and Part B generally only covers outpatient care and some preventative care. Prescriptions taken outside of the hospital will not be covered by Medicare Part A or Medicare Part B. Medicare Part D therefore, is designed to help cover prescription drug costs. One does still have to pay both a copay and deductible.
Medicare is available for US citizens aged 65 and older. You also may be eligible if you are under 65 years old and certain disabilities. Also those with End Stage Renal Disease may also be eligible for Medicare coverage.
You will automatically be enrolled in Medicare once you turn 65 if you are already receiving social security benefits. If not, you will need to apply yourself 90 days before your 65th birthday. Once you have been enrolled in Medicare you will be signed up for both Medicare Part A and Part B. At that point you can choose to keep your Medicare Part B coverage or decline it. There is a cost for Medicare Part B.
It is recommended to sign up for Medicare Part D when you initially sign up for your Medicare insurance. If you choose to wait and enroll later, there will be an additional fee. Medicare Part D can also be bought from a PPO or HMO, a third party insurer.