Open Enrollment: How to Pick a Plan That Covers Your Medication

Open enrollment is one of those things that most people treat as a chore — clicking through plan options, comparing premiums and deductibles, and ultimately just picking whatever seems cheapest or sticking with what they had last year. That approach works fine if your healthcare needs are basic.

But if you're taking or hoping to take a GLP-1 medication like Wegovy or Zepbound, open enrollment is a critical decision point. The plan you choose can mean the difference between a medication that's covered with a manageable out-of-pocket cost and one that isn't covered at all.

This article gives you a practical framework for evaluating plans based on drug coverage — so you can make this decision with your eyes open.

When Is Open Enrollment?

Before diving into how to pick a plan, a quick orientation:

• Employer-sponsored insurance: Open enrollment is typically in the fall (often October or November) for coverage that begins January 1. The exact dates are set by your employer, and missing the window means you're generally stuck with your current plan until the following year (unless you have a qualifying life event like marriage, job change, or birth of a child).
• ACA Marketplace plans: Open enrollment typically runs from November 1 through January 15 in most states. Some states have their own exchanges with slightly different windows. Coverage picked by December 15 usually starts January 1.
• Medicare Part D and Medicare Advantage: Open Enrollment runs October 15 through December 7 each year, for coverage beginning January 1.
• Medicaid: There's no annual enrollment window — eligibility is based on income and other criteria, and you can apply at any time.

Step 1: Know Exactly What You Need

Before you evaluate any plan, get specific about what you need it to cover:

• The exact medication name. Not just "a GLP-1" — the specific brand name your doctor has prescribed or is likely to prescribe. Different plans cover different drugs; if you don't have a specific medication yet, ask your doctor which one is most likely.
• The dose and quantity. Higher doses sometimes have different formulary listings or quantity limits.
• Any other ongoing medications. If you're on other prescriptions, check those too — a plan that covers your GLP-1 but not your blood pressure medication isn't a clear win.

Step 2: Look Up the Formulary Before Comparing Anything Else

Most people compare plans by looking at premiums, deductibles, and copays. Those things matter — but if the medication you need isn't covered, a low premium is meaningless.

Here's how to check formulary coverage before doing anything else:

For employer plans: Your HR department should be able to provide the formulary for each plan option during enrollment. If not, the plan documents or your insurer's website should include a drug search tool. Ask HR: "Which of these plan options covers [medication name]?"

For ACA Marketplace plans: At healthcare.gov (or your state's marketplace), you can compare plans and search for specific medications within each plan. Look for the "Drug Coverage" or "Plan Formulary" tab when viewing plan details. Type in your medication name and check whether it's covered, at what tier, and what restrictions apply (PA, step therapy, quantity limits).

For Medicare Part D: The Medicare Plan Finder at medicare.gov lets you enter your medications and find plans that cover them. This tool also shows estimated annual drug costs across plans, which is especially useful for expensive medications.

Don't trust general descriptions like "comprehensive drug coverage" or "extensive formulary." Look up your specific medication by name.

Step 3: Read the Restrictions, Not Just the Coverage Status

Finding your medication on a plan's formulary is necessary but not sufficient. Look carefully at what restrictions are attached:

• Prior Authorization (PA): Almost universal for GLP-1s on commercial plans. This means your doctor will need to get approval before the plan pays. It doesn't make a plan bad — it's the norm — but know it's coming.
• Step Therapy (ST): Check whether the plan requires you to try another medication first. If you've already tried step-therapy drugs in the past, your doctor may be able to document this and skip the step. But if you haven't, you'll need to factor this into your timeline.
• Quantity Limits (QL): Make sure the plan's quantity limit matches your expected dosing. A plan that limits to one pen per month when you're on a higher maintenance dose will cause coverage gaps.
• Specialty tier: If the medication is on a specialty tier, ask whether your plan has specialty tier cost-sharing (often coinsurance rather than a flat copay, and sometimes subject to your deductible).

Step 4: Calculate Your Actual Annual Drug Cost

Once you know a medication is covered and at what tier, estimate what you'll actually pay. This calculation isn't just the copay — it includes:

1. Deductible: Does your plan have a separate drug deductible? Some plans require you to meet a deductible before drug benefits kick in, even for covered medications.
2. Cost-sharing: Once the deductible is met, what's your copay or coinsurance for specialty drugs?
3. Out-of-pocket maximum: If you hit your plan's out-of-pocket maximum, your covered drugs become free for the rest of the year. For expensive medications, this can be meaningful.

Compare this calculation across the plans you're considering. A plan with a higher premium but better drug coverage may actually cost you less overall if your medication is expensive.

For Medicare Part D specifically: Use the Plan Finder's drug cost estimator, which does this math for you based on the medications you enter. For expensive specialty medications, the annual cost comparison across Part D plans can vary significantly.

Step 5: Think About the Full Year, Not Just the First Month

A few timing-related things to keep in mind:

The "new plan year" PA reset: Many insurance plans require a new prior authorization at the start of each plan year, even if you were previously approved. If you're switching plans, expect your new plan to require its own PA process from scratch.

Step therapy and continuity: If you've been stable on a medication and you switch to a plan that has step therapy requirements, you may be protected by continuity-of-care rules — but this isn't guaranteed, especially if you're switching to a completely new type of plan. Ask your doctor's office about this before you switch.

Specialty pharmacy requirements: Some plans require specialty medications to be filled through a designated specialty pharmacy rather than a retail pharmacy. This affects where you pick up your medication and sometimes how quickly you receive it. It's worth knowing in advance.

Step 6: Look at Quality Ratings, Not Just Cost

When comparing plans on the ACA marketplace or Medicare Advantage, look at plan ratings (CMS uses a star rating system for Medicare plans). Higher-rated plans tend to have better customer service, fewer administrative problems, and faster appeals processing — all of which matter more than you'd expect once you're navigating prior authorizations.

If No Available Plan Covers Your Medication

Sometimes, especially with employer insurance, none of the plans offered cover your medication. In that case:

• Talk to HR about whether coverage could be added in future plan years
• If you're in a two-income household, check whether a spouse's plan has better coverage
• For ACA marketplace plans, expand your search to all available plans in your area — coverage can vary significantly between plans
• Consider manufacturer patient assistance programs as a bridge

See our article on what to do if your plan doesn't cover obesity medications at all for a deeper look at these alternatives.

The Bottom Line

Open enrollment is the one time each year when you have real control over your insurance coverage. For patients who need GLP-1 medications, using that window wisely — by doing the formulary research before picking a plan — can make an enormous practical difference.

The homework is tedious. But picking a plan that covers your medication at a manageable cost is worth the two hours it takes to do it right.