ERI message on your patient programmer – What does it mean?


Neurostimulator battery checks are important to maintain on a schedule. When you visit with your doctor, the battery status is one of the maintenance check points that your doctor reviews. These check-ups are important so that you do not suddenly lose therapy. Sudden and/or unexpected neurostimulator depletion can also indicate a problem with the implanted system. Neurostimulator maintenance check-ups can help you avoid problems that may interrupt your therapy. The following describes the neurostimulator battery messages you will see over time.

ERI = Elective Replacement IndicatorERI3


When you check your neurostimulator, you will either see OK, ERI or EOS displayed on the screen. OK means your neurostimulator battery is in good status. ERI is a message displayed on the patient programmer screen when the Medtronic neurostimulator is nearing end of life. This message is important to report to your doctor. When the ERI appears, you will have a short time to have the neurostimulator replaced before losing therapy. The time-frame to reach neurostimulator depletion (end of life) depends on your energy usage (stimulation settings). The pictures on the right depict the various ERI messages possible on the patient programmer display screen.

EOS = End of Service


You should call your doctor immediately if you see the EOS message displayed.



  1. Ramona Edwards says:

    Is there a range of voltage readings that the Activa PC will need to be replaced at? I have bilateral stims and they are at 2.80 and 2.82 and going down at a rate of .01 every 2-3 weeks, but I am not getting the ERI message yet. Would appreciate input?

    1. DBSProgramming says:

      Yes, a PC voltage reading of 2.6 indicates your PC has reached the elective replacement stage (ERI) in battery depletion. Once the PC reaches 2.2 volts, battery replacement is urgent to avoid sudden loss of power (EOS).

Leave a Reply