What to do if…
your glucose monitor or insulin device alarms and you are not sure what it means

What to do now

1. Check how you feel first. If you feel low, such as shaky, sweaty, weak, confused, or have blurred vision, treat it as low blood sugar right away.
2. If possible, check a fingerstick glucose now. Use the fingerstick result and your symptoms if the CGM number does not seem right.
3. If your blood sugar is low, often under 70 mg/dL, below your personal low threshold, or you feel low: take 15 grams of fast-acting carbohydrate, wait 15 minutes, then recheck. Repeat if you are still low. Once you are back up and steady, eat a meal or snack if your next meal is not soon and that is part of your plan.
4. If someone cannot swallow safely, is unconscious, or is having a seizure: call 911 immediately. If glucagon is available and someone present knows how to give it, use it while waiting for emergency help.
5. Read the alarm message and put it into one simple bucket.
   • Low or urgent low: treat first.
   • High: confirm with a fingerstick if you can; if you feel sick, check ketones if you have supplies.
   • Delivery problem, occlusion, no delivery, or pump stopped: assume insulin may not be getting in.
   • Sensor error, signal loss, calibration required, or app disconnected: assume the reading may be unreliable.
   • Low reservoir, low battery, or change set or sensor soon: fix it after you have checked that you are safe.
6. If a pump alarm suggests insulin delivery failed, act like insulin may be interrupted. Check whether the pump is suspended or stopped, tubing is kinked, the site is loose, painful, wet, or leaking, the cartridge or reservoir is empty, or the insulin may be spoiled or expired. If you can, change the infusion set or site and insulin using your device instructions.
7. Use your backup insulin plan if pump delivery is not reliable. Many people are told to use insulin pens or syringes temporarily when pump delivery fails. If you do not have a clear backup plan, call your diabetes clinician, after-hours line, or device support rather than guessing doses.
8. If glucose is high and you feel unwell, especially if you use a pump: check ketones if you have urine strips or a blood ketone meter. Call your clinician urgently or seek urgent care if ketones are moderate or high by your strip or meter instructions, you are vomiting, you have severe abdominal pain, deep or rapid breathing, fruity-smelling breath, confusion, extreme sleepiness, or you cannot keep fluids down.
9. If the alarm comes through a phone or app: reduce the risk of missing the next alert. Check volume, silent mode, Do Not Disturb or Focus settings, notification permissions, Bluetooth connections, and battery saver settings. Then confirm the alarm status on the device or app.
10. Stabilize the next hour. Tell someone you trust what is happening and ask them to check in. Keep fast carbs, your meter and strips, ketone supplies if you use them, and glucagon nearby. Recheck until you feel steady and the readings make sense.