Thinking about a continuous glucose monitor (CGM)? You're not alone. CGMs have become a common tool for people with diabetes, and there are more options than ever. That's good news, but it can also make the decision feel a little overwhelming.
The good news is you don't have to figure it out alone. This guide to choosing a CGM covers the questions worth asking your care team, your insurance plan, and yourself, so you can find a device that fits your health needs and your daily life. If you're new to CGMs, start with our CGM basics guide.
Is a CGM right for me?
Whether to use a CGM is a decision to make with your healthcare team. The American Diabetes Association's Standards of Care discuss CGM use for many people with diabetes, especially those who take insulin, but the right choice depends on your treatment, your goals, and how you'd use the data.
Questions to ask your care team:
- Would a CGM help with my diabetes care right now? What would we use the data for?
- Would a prescription CGM or an over-the-counter option make more sense for me?
- Do I still need to use a fingerstick meter sometimes? When?
- How will we review my CGM data together, and how often?
- Is there someone at the clinic, like a diabetes educator, who can help me get started?
People with type 1 diabetes and people who use insulin pumps may have extra things to consider, like whether a CGM works with their pump. Your care team can help you sort through that.
Insurance and cost questions
Cost and coverage often shape which CGM you end up with. Coverage varies widely by plan, so it's worth making a few calls before you decide.
- Is a CGM covered by my plan? If so, which devices, and what do I need to qualify?
- Is prior authorization needed? Some plans need paperwork from your provider before they'll cover a CGM.
- Pharmacy or medical equipment benefit? Some plans cover CGMs through the pharmacy, and others through durable medical equipment (DME) suppliers. This can change where you pick up supplies and what you pay.
- What will I pay out of pocket for sensors and any other parts, and how often will I need refills?
- Are there savings programs or lower-cost options if coverage is limited?
If cost is a barrier, tell your care team. They may know about other options or programs that can help.
Wear time, warm-up, calibration, and accuracy
CGMs differ in how they work day to day. These questions can help you compare options without getting lost in technical details:
- Wear time: How many days does each sensor last before I replace it?
- Warm-up: How long after inserting a new sensor before readings start?
- Calibration: Does it need fingerstick calibration, or is that optional?
- Accuracy: When should I double-check with a meter, for example when symptoms don't match the reading?
- Medicines and interference: Are there any medicines or supplements that can affect readings with this device?
- Insertion: Where on the body is it worn, and how is it applied?
Keep in mind that a CGM measures glucose in the fluid under your skin, not directly in your blood. That means readings can lag behind a fingerstick, especially when glucose is changing quickly. Your care team can explain what this means for the device you're considering.
Apps, alerts, data sharing, and privacy
For many people, the app is where they spend the most time with their CGM. It's worth checking the details before you commit.
- Phone compatibility: Does the app work with my phone and its operating system? Is there a separate reader if I need one?
- Alerts: Can I set alerts for highs and lows? Can I adjust them so they're helpful, not overwhelming?
- Trend arrows and reports: How does the app show where glucose is heading? Our guide to CGM trend arrows and reports explains the basics.
- Sharing with family: Can a family member or caregiver follow my readings if I want them to?
- Sharing with my clinic: Can my care team see my reports before or during visits?
- Privacy: Who can see my data? How is it stored, and can I control or delete it? Reading the privacy policy is worth a few minutes.
Lifestyle fit: skin, sports, water, and travel
The best CGM is one you'll actually wear. Think about your day-to-day life:
- Skin and adhesive: Do I have sensitive skin? What can I do if the adhesive irritates my skin or doesn't stick well?
- Sports and activity: Will the sensor stay put during the activities I enjoy? Are there overpatches or tips for keeping it secure?
- Water: Can I shower, swim, or bathe with it? Are there limits on depth or time?
- Travel: How do I handle airport security and time zones with this device?
- Comfort and visibility: Where can I wear it so it's comfortable with my clothes, sleep position, and work?
Your printable questions for choosing a CGM
Copy these questions onto a notecard or into your phone and bring them to your next visit or call:
- Would a CGM help my diabetes care, and how would we use the data?
- Prescription or over-the-counter: which fits my needs?
- When will I still need a fingerstick meter?
- Is it covered by my insurance? Is prior authorization needed?
- Is it covered through my pharmacy or medical equipment (DME) benefit?
- What will I pay for sensors and supplies?
- How long does each sensor last, and how long is the warm-up?
- Does it need calibration?
- Can any medicines or supplements affect readings?
- Does the app work with my phone? Can I adjust alerts?
- Can I share data with family and my clinic?
- Who can see my data, and how is it protected?
- Does it work with my insulin pump, if I use one?
- What if the adhesive bothers my skin?
- Can I swim, shower, and exercise with it?
- Who can help me get started and troubleshoot?
Want to see how different devices look in daily life? Browse our product reviews for hands-on overviews, and use them alongside advice from your care team.
When to talk to your care team
Talk with your care team before starting a CGM and any time you have questions about your readings. Reach out if your CGM numbers often don't match how you feel, if you're getting frequent low or high alerts, or if skin irritation keeps you from wearing it. Never change your medication or insulin based on CGM data unless it's part of the plan you've made with your team.
A CGM is a tool, not a test you pass or fail. The right questions can help you choose one that supports your care and fits your life.
