Transcutaneous Electrical Nerve Stimulation (TENS)
A TENS machine is sometimes suggested to people in pain. It is a treatment that uses low voltage electrical currents to relieve pain. It is in the form of a portable (small) machine which sends the low voltage current through the skin once the device is connected.
Again we referred to the Cochrane reviews to find out more about the evidence for using TENS machines for chronic pain. A review was published in 2008 which does not help us evaluate whether to use TENS or not for generalised persistent pain:
"Despite the widespread use of TENS machines, the analgesic effectiveness of TENS still remains uncertain. This has mainly been due to inadequate methodology and reporting in earlier studies but more recent studies of TENS for chronic pain fail to offer necessary improvements in methodological rigour to define the place of TENS in chronic pain management with any certitude. The search process identified 124 studies; 25 met the inclusion criteria for evaluation in this review but there were insufficient extractable data to make meta-analysis possible. New studies of rigorous design and adequate size are needed before any evidence-based recommendations can be made for patients or health professionals.” (Nnoaham & Kumbang 2008)
Some people say that TENS is really helpful for them, others don’t. Using a TENS machine is therefore highly individual. It is, like other strategies, something that may be a part of your pain management strategy, but not the whole of it.
Who should not use TENS?
There are some people however who should not use TENS machines, including those with a pacemaker, those who have epilepsy and are using the machine alone, those in the first trimester of pregnancy and if you have a cochlear implant. Don’t use it on broken skin or over your face or the front of your neck.