A TENS machine (Transcutaneous Electrical Stimulation) is a small device that emits electrical impulses through the skin. It aims to disrupt the pain messages sent to the brain on a higher frequency (Hz), or gives pain relief by releasing endorphins and blocking pain signals at a lower frequency (Hz). Either high frequency or low frequency may provide pain relief (Han et al 2022)
Do not use TENS if:
- you have a pacemaker
- have broken skin in the area
- have poor or no sensation in the area
- have epilepsy
- are pregnant
How does TENS work to reduce pain:
Pain Gate Mechanism: this is essentially closing the gate to the pain message to the brain by exciting the A Beta nerve fibres which inhibits the C fibres (that sends the pain message).
Endorphin Release Mechanism: This setting stimulates the A delta fibres which release endorphins from the spinal cord and inhibits the C fibres from transmitting pain signals.
How to choose the right settings:
Some TENS have pre-set settings with a few options. You may need to try a few options and see which provides you the most pain relief.
For the machines that have more freedom on settings such as the ProTENS you can program the right setting for you controlling the following:
Pulse width: 100 or 200us
Pulse Rate: 2-10Hz or 50-130Hz
Frequency for Pain Gate Mechanism: 50-130Hz and 100us
Frequency for Endorphin release: 2-10Hz and 100-200us
Continuous or Pulsed: Continuous is more tolerable for people with pain
Intensity: This can be adjusted by a dial or button depending on your machine
The most important parameter is the intensity, which should be set to a nonpainful, maximal tolerable intensity level (Elboim-Gabyzon, Kalichman, 2020).
Duration
One study has reported 20-30 minutes is the minimum amount of time (Elboim-Gabyzon, Kalichman, 2020).
How often
There is no consistent clinical research on the benefits of how often TENS is used. But there is evidence of becoming tolerant to settings and there is a need to increase the intensity (not the Hz) to have the same desired pain relief over time (Elboim-Gabyzon, Kalichman, 2020).
TENS is more effective for reducing pain during movement when compared with resting (Elboim-Gabyzon, Kalichman, 2020).
Selecting the right machine
There are many machines on the market ranging from $50 – 200. If you are just using TENS for pain management and you prefer a discreet under the clothes a cord free option then a Vush-Aura or similar will be suitable. However, if you are also using TENS for overactive bladder, faecal urgency, or constipation then select a machine that allows you to control the settings such as ProTENS.
ProTENS
- Allows you to have full control over settings
- Battery operated
- Can be used for overactive bladder, constipation, pain management, faecal urgency
- Device needs to be held, clipped to clothing or kept in pocket
- Price guide $54 + shipping
www.myphysioshop.com.au
Vush Aura TENS
- No cords so can be worn discreetly under clothes
- 5 hours of charge time
- USB chargeable
- Medical Grade silicone
- Price guide $75 + shipping
PELVI Pulse TENS
- No cords so can be worn discreetly under clothes
- 5 hours of charge time
- USB chargeable
- Price guide $90 + shipping
MiraPro TENS + Heating
- TENS and heating in one
- No cords so can be worn discreetly under clothes
- 5 hours of charge time
- USB chargeable
- Price guide $200 + shipping
References
- Arik MI, Kiloatar H, Aslan B, Icelli M. The effect of TENS for pain relief in women with primary dysmenorrhea: A systematic review and meta-analysis. Explore (NY). 2022 Jan-Feb;18(1):108-113
- Elboim-Gabyzon M, Kalichman L. Transcutaneous Electrical Nerve Stimulation (TENS) for Primary Dysmenorrhea: An Overview. Int J Womens Health. 2020 Jan 8;12:1-10.
- Han S, Park KS, Lee H, Kim E, Zhu X, Lee JM, Suh HS. Transcutaneous electrical nerve stimulation (TENS) for pain control in women with primary dysmenorrhoea. Cochrane Database Syst Rev. 2024 Jul 22;7(7)