When you shop for a new car or truck, you don’t just buy the first one you see, do you?

Probably not. You shop around, looking for the best deal you can get on a vehicle that fits your driving needs as well as your pocketbook.

Well, it’s the time of year when you can shop for a Medicare health or drug plan.

Medicare’s open enrollment period began Monday and runs through Dec. 7.

If you have Original Medicare, meaning that you can choose any doctor or hospital that accepts Medicare, you don’t need to think about open enrollment.

But if you have a Medicare Advantage (Part C) health plan or a Medicare (Part D) prescription drug plan, you might want to see whether there’s another plan on the market that would be a better match for you, at a lower price.

If you’re enrolled in a plan and you’re happy with it, you don’t need to do anything.

But Medicare health and drug plans — run by private insurers approved by Medicare — can change from year to year. A plan can raise its monthly premium or drop a medicine that you need.

So it makes good sense to review your coverage each year. Make sure your plan still is a good fit for you in terms of cost, coverage and quality.

If it isn’t, look for another plan.

During open enrollment you can sign up for a Medicare Advantage health plan or Part D prescription drug plan, or switch from one plan to another. Your new coverage will take effect Jan. 1.

How do you shop for a new plan?

One way is the “Medicare & You” handbook, mailed each fall to every Medicare household in the country. This booklet lists all the Medicare health and drug plans available where you live, along with basic information such as premiums, deductibles and contacts.

There’s also the Medicare Plan Finder, at Medicare.gov.

Look for a green button that says, “Find health & drug plans.” Click on that, plug in your ZIP code and you’ll see all of the Medicare Advantage and Part D plans available in your area. You can compare them based on benefits, premiums, copays and estimated out-of-pocket costs. Contact information for the plans is listed.

The Medicare.gov website also can help you decide whether Original Medicare or Medicare Advantage is better for you, and can help estimate your out-of-pocket costs with either type of coverage.

Each Medicare health and drug plan has been assigned a rating of from one to five stars, with five stars being the best in terms of quality.

If you don’t have access to a computer, call 800- MEDICARE (800-633-4227). Our customer service representatives can help you with questions about Medicare health and drug plans. The call is free.

Another terrific resource is the State Health Insurance and Counseling Program.

SHIP is an independent, nonprofit organization that provides free, personalized counseling to people with Medicare. You can make an appointment to speak with a SHIP counselor in person or over the phone.

SHIP counselors are well-trained volunteers who often are enrolled in Medicare themselves, so they know the issues. They can help you sort through different health and drug plans and find one that’s right for you. They’re not salespeople, and they won’t try to sell you a specific plan.

To contact your local SHIP office, go to shiptacenter.org.

If you’re enrolled in a Medicare Advantage plan as of Jan. 1 but you’re not satisfied with it, you have a three-month window to dis-enroll. Between Jan. 1 and March 31 you can drop your plan and return to Original Medicare (and join a stand-alone Medicare prescription drug plan).

Having trouble paying for your Part D plan? You may be eligible for the Extra Help program, which helps cover your premiums, deductibles and copays. Medicare beneficiaries typically save about $4,000 annually with Extra Help.

For more information about Extra help, go to SSA.gov/prescriptionhelp.

Greg Dill is Medicare’s regional administrator for Arizona, California, Nevada, Hawaii and the Pacific territories. You can always get answers to your Medicare questions by calling 800-MEDICARE (800-633-4227).