What is a TENS Unit

What is a TENS unit?

TENS, or Transcutaneous Electrical Nerve Stimulation, is the use of electrical impulses delivered by a TENS unit via TENS electrodes placed on the skin in order to create alterations in pain perception.  A home TENS unit is easy to use for symptomatic pain relief including joint pain and muscle pain.

How to use a TENS unit?

Place the electrodes according to the instructions included with the unit in order to ensure safe and effective use of the TENS unit.  Slowly turn the intensity up until you first feel a tingling or buzzing sensation.  You can then continue to increase the intensity until it feels strong but comfortable.   TENS units often have different programs that feel different (pulsing versus tingling, constant versus on and off).  Trying these different programs give you the opportunity to see what feels the best and provides the most pain relief.


How long do I use the TENS unit?

It is a good idea to start with a 10-15 minute program to see how your body responds. In total, it is safe to use for up to 30 minutes.

How does a TENS unit work to relieve my pain?

The electrical impulses from the TENS unit excite the sensory nerves.  This can provide varying degrees of pain relief by activating the body’s natural pain relieving system and/or the nervous system’s ability to use the electrical impulses to interfere with the pain messages being sent to the brain.

Is a TENS unit ok for me to use at home?

There are a number of reasons to try a home TENS unit to assist with pain relief.  TENS units are easy to use, are non-invasive, and have minimal side effects.

Is there a reason that I should not use a TENS unit?

Most people can safely and effectively use a home TENS unit to obtain pain relief.  Occasionally, there are reasons to not use a TENS unit.  These include the following:

  • Pregnancy
  • Pacemaker or any implanted electronic device
  • Over skin lesions
  • Over the front of the neck/carotid artery
  • On the head

If you have any questions about TENS units and whether or not electrotherapy is right for you, please consult with a medical professional like a PT (Physical Therapist).


By Kathy Primpin, PT (Physical Therapist), MPT, OCS, Cert MDT, COMT