Although often described as a 90 day lifespan, the Dexcom G5 Transmitter actually lasts a bit longer.
Note: This is specifically when running the Dexcom G5 Transmitter with the Dexcom Receiver, the Tandem t:slim X2 pump and/or the Dexcom G5 Mobile App.
You should be able to get a minimum of 106 days out of the transmitter and potentially 112 days.
A sensor start will only work if you can still get a full 7 days from the existing transmitter.
If the sensor is restarted on Day #106 (which is date of transmitter activation plus 105 days) then it should work and allow another 7 days on that transmitter up to Day #112.
If the sensor is restarted one day later (ie - on Day #107) than a message will be displayed indicating the transmitter needs to be replaced and the session is not allowed to be started.
The easiest way to “count days” is with MS Excel. Put the transmitter activation date in one cell. Put the number of days to add, 105 into the next cell. Add these cells together and it should result in a date which is 105 days out. (105 days out is Day #106.) Put a reminder on your calendar that this day is the last possible sensor restart for this transmitter.
Being able to run the transmitter for 112 days as opposed to the advertised 90 days results in a 25% increase.
At a minimum, you should be able to get 106 days which is almost 18% greater than advertised.