Transcutaneous electrical nerve
stimulation (TENS) is a therapy that uses low-voltage electrical current for
You do TENS with a small, battery-powered machine
about the size of a pocket radio. Usually, you connect two electrodes (wires
that conduct electrical current) from the machine to your skin. The electrodes
are often placed on the area of pain or at a pressure point, creating a circuit
of electrical impulses that travels along nerve fibers.
current is delivered, some people experience less pain. This may be because the
electricity from the electrodes stimulates the nerves in an affected area and
sends signals to the brain that block or "scramble" normal pain signals.
Another theory is that the electrical stimulation of the nerves may help the
body to produce natural painkillers called endorphins, which may block the
perception of pain.
You can set the TENS machine for different
wavelength frequencies, such as a steady flow of electrical current or a burst
of electrical current, and for intensity of electrical current. Your physical
therapist, acupuncturist, or doctor usually determines these settings.
After you receive an introduction to and instruction in this therapy, you
can do TENS at home.
What is TENS used for?
People use TENS to relieve
pain for several different types of illnesses and conditions. They use it most
often to treat muscle, joint, or bone problems that occur with illnesses such
fibromyalgia, or for conditions such as low back pain,
bursitis. People have also used TENS to treat sudden
(acute) pain, such as labor pain, and long-lasting (chronic) pain, such as
Although TENS may help relieve pain for some people,
its effectiveness has not been proved.
Is TENS safe?
Experts generally consider TENS to be
safe, although the machine could cause harm if misused. Have your physical
therapist or doctor show you the proper way to use the machine, and follow
these instructions carefully.
Always tell your doctor if you are
using an alternative therapy or if you are thinking about combining an
alternative therapy with your conventional medical treatment. It may not be
safe to forgo your conventional medical treatment and rely only on an
Primary Medical Reviewer
Adam Husney, MD - Family Medicine
Specialist Medical Reviewer
Marc S. Micozzi, MD, PhD - Complementary and Alternative Medicine
How this information was developed to help you make better health decisions.