A Clinician's Triage Guide to Troubleshooting CGM Alarms and Alerts

CGM 101 · Clinician's Playbook

When CGM alerts aren't working for the person

CGM alert concerns often surface during routine diabetes care. Sometimes the alert fires too often, sometimes it never reaches the person and sometimes it reaches them but they can't act on it. Each has a different fix. This guide is a decision process for sorting them out.

Alert fatigue Heavy sleepers Access & ability needs

A clinical decision aid

Triage first, then match the option

Rather than jump to a specific tip, this guide starts with the reason the alert is failing: confirm it's actually reaching the person, sort the mechanism, then match a first step. Sorting by cause makes it easier to choose a sensible fix and avoid making an unnecessary alert louder.

Important NOte: Some options are device features; others Listed are Off-label user-developed workarounds

Start with the CGM's approved alert settings, accessibility options, compatible devices and sharing features. Some additional approaches, such as placing a vibrating phone in a hard container or connecting alerts to third-party accessories, are user-developed workarounds that have not been validated by the CGM manufacturer. They should supplement, not replace, the primary CGM alert. Confirm the approach doesn't interfere with required alerts, review current manufacturer instructions and individualize the plan.

Step 1 · Triage

Before you reach for a fix, ask one question

Open with

"Walk me through the last time an alert went off — or should have. What happened?"

First, confirm the alert is actually being generated and delivered

Amplifying a notification that never fired does nothing. Check the CGM app, connectivity, notification permissions, sound and volume settings, compatible phone/OS, battery optimization, watch routing and any signal-loss messages. If the alert is arriving but isn't working for the person, sort it below.

Tune

"Too many. I tune them out."

Alert fatigue. Alerts arrive, but too often, too early or for readings that resolve on their own. Direction: fewer, more actionable alerts, while preserving clinically important lows.

Troubleshoot

"It doesn't consistently arrive."

Delivery gap. Signal loss, Bluetooth, range, permissions, an OS update or app restrictions are dropping the alert. Direction: restore reliable delivery before anything else, and involve manufacturer support when settings are correct.

Amplify

"It arrives, but I don't notice it."

Perception gap. The alert is delivered and correct; it simply isn't reaching the person through their current channel. Direction: louder, larger or a different sense.

Support

"It arrives, but I may not respond on my own."

Response-support need. Vision, hearing, dexterity or cognition may limit an independent response. Direction: an additional support pathway plus a caregiver response and hypoglycemia safety plan, not a louder alert alone.

Alert burden may reflect the glucose pattern, not the settings

If alerts are frequent because clinically important highs or lows are recurring, review the underlying treatment plan (overnight hypoglycemia, post-meal highs, insulin timing, overtreatment or compression lows) rather than simply reducing notifications.

Step 2 · Match the option

Start with supported settings, then add hardware

Begin with the CGM's approved settings and existing devices, then add hardware when the person's access needs or sleep pattern call for it. Test each setup with the person rather than assuming it works.

Tier 1

Supported settings & habits

Approved features and no-cost changes. Verify behavior on the person's specific device.

Reduce alerts that aren't actionable

Review which alerts are firing, whether they're actionable and how often they repeat. Consider adjusting optional high alerts, rise-rate alerts, repeat intervals or first-alert delays when the device permits.

Be more cautious changing low or predictive-low alerts, especially with impaired hypoglycemia awareness, recurrent severe hypoglycemia, pregnancy or limited ability to respond. Alert names, thresholds and sound behavior vary by CGM; for example, Dexcom G7 includes a required Urgent Low Alert at 55 mg/dL, but verify the person's specific device, app and phone settings before changing anything.

Alert fatigue

Try a different available alert sound

If the person has grown accustomed to a recurring alert sound, switching to a distinctly different available tone may help some people notice it again. Confirm which sounds can be changed on the specific CGM and phone. Not every system allows every tone to be changed.

Alert fatigue

Critical Alert / DND override (approved)

On supported iPhones, Critical Alerts may allow an authorized CGM app to deliver selected alerts through mute or Focus settings. Some Android CGM apps offer a Do-Not-Disturb override or high-priority notification setting, but behavior varies by CGM, phone model, OS and app permissions. Test the setup with the person rather than assuming it works.

All mechanisms

Tier 2

Added hardware & workarounds

A modest purchase. Some manufacturer-supported, some user-developed. Maintain the CGM's standard alert pathway.

Bed-shaker / vibrating pad

Bed-shaker alarm systems provide a non-audio waking cue and may help people who are Deaf, hard of hearing or difficult to wake. Connecting one to CGM notifications may require third-party hardware or automation that hasn't been validated by the CGM manufacturer. Confirm compatibility and keep the CGM's standard alert pathway intact.

Heavy sleepers · hearing

Second display: supported or unofficial

Manufacturer-supported receiver or compatible display: when available, an approved receiver may add a second display and alert pathway; check whether the CGM allows simultaneous phone-and-receiver use. Unofficial secondary display: community-built or third-party displays may show glucose in large digits across a room, but compatibility, alert behavior, data delay, privacy and regulatory status vary. Don't use one as the sole source for treatment decisions or urgent alerts.

Low vision · overnight

Tier 3

Sharing & wrist cues

Route an additional cue to another device or support person, as a supplement, never a replacement.

Share / Follow as added support

Use remote monitoring as an additional support pathway when the person may not reliably notice or respond to alerts. Clarify who receives alerts, which alerts they receive, what response is expected and what to do if data are delayed or unavailable. Remote monitoring should not replace the person's primary CGM display, individualized safety plan or emergency response plan. LibreLinkUp and Dexcom Follow are designed to assist designated people, not to serve as a primary monitor.

Response-support need

Compatible smartwatch cue

A compatible smartwatch can provide a wrist-based visual and haptic cue for people who miss phone sounds, particularly during waking hours. It may help some sleepers but shouldn't be assumed to awaken a person reliably. Confirm whether the watch mirrors the phone or connects directly to the CGM, what distance and connectivity are required and how urgent alerts behave.

Hearing · daytime cues

Step 3 · Access needs

Match the alert pathway to the access need

Access needs are not one audience, and a single catch-all approach underserves all of them. Match the alert pathway to the specific need, and don't assume the default audio path works.

Low vision / blind

For low vision, consider high-contrast or large-format displays when usable. For blindness, prioritize reliable audio, screen-reader access, tactile or haptic cues and accessible treatment supplies. Verify the person's actual CGM app and workflow with VoiceOver or TalkBack rather than assuming compatibility.

Deaf / hard of hearing

Don't rely on audio as the primary path. Some people may benefit from amplification or a different frequency, but build the plan around haptics (watch, bed shaker) and visual cues. Verify the person can tell an urgent alert from a routine notification by feel or sight alone.

Dexterity / motor

The bottleneck is responding, not hearing. Pre-stage fast-acting carbs within reach and simplify the steps to silence and act. Consider remote monitoring as an additional way for a support person to recognize a possible problem, and separately establish how the person will request help (voice calling, an accessible emergency button or another individualized method).

Cognitive / memory

Keep alerts limited to those the person and support team can understand and act on, without disabling clinically important safety alerts. Use consistent wording, an explicit response plan and additional caregiver monitoring when appropriate.

At the point of care

The 90-second visit script

Surface it

"Tell me about the last alert you missed, or one that fired when you didn't need it."

Confirm delivery

Is the alert being generated and delivered (app, connectivity, permissions, volume, OS)?

Sort it

Tune, troubleshoot, amplify or add response support?

Frame any workaround

"This isn't a manufacturer-validated feature. Some find it a helpful extra cue, but it shouldn't replace your regular alert. Let's make sure it doesn't interfere and decide how you'll know it's working."

Document & revisit

Alert settings and response plans often need to be revisited. Note what changed and recheck.

Know when this isn't an alert-setting problem

Contact manufacturer technical support for repeated signal loss, missing alerts despite correct settings, app failures, sensor errors or compatibility problems.

Address recurrent or severe hypoglycemia, loss of consciousness, inability to self-treat or unsafe overnight patterns through the person's clinical and emergency plan, not solely through louder alerts.

A note on shelf life

Alert names, required settings, thresholds, sound behavior, OS support and hardware compatibility change often and differ by CGM. Verify device-specific details against the manufacturer's current instructions for use before recommending and treat dated product mentions as starting points, not endorsements. This content is educational and does not constitute medical advice. Always individualize to the person's clinical needs.

Pair this with the point-of-care card

Keep the one-page triage card in the exam room for use mid-visit; this explainer is the background behind it. Together they cover both the "learn it once" need and the point-of-care moment: confirm delivery, sort the mechanism and match one option.

Help patients get the alert that actually reaches them

An alert only helps once it's noticed and actionable

Confirm delivery, sort the mechanism, match one option and coach it in plain language. Small settings changes at the point of care often resolve what looks like a hardware problem.

Explore more CGM 101 resources

Find the point-of-care triage card, alert-setup guides and more practical tools from danatech.

Browse CGM 101

User-developed workarounds supplement, never replace, the device's validated alert, individualized safety plan and emergency response plan. This content is educational and does not constitute medical advice. Always individualize to the person's clinical needs and defer to the manufacturer's current instructions for use.

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DISCLAIMERS: 

This site and its services do not constitute the practice of medical advice, diagnosis or treatment. Always talk to your diabetes care and education specialist or health care provider for diagnosis and treatment, including your specific medical needs. If you have or suspect that you have a medical problem or condition, please contact a qualified health care professional immediately. To find a diabetes care and education specialist near you, visit the ADCES finder tool.

ADCES and danatech curate product specifics and periodically review them for accuracy and relevance. As a result, the information may or may not be the most recent. We recommend visiting the manufacturer's website for the latest details if you have any questions.

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