What Is TENS Unit Therapy?

TENS, or transcutaneous electrical nerve stimulation, is a drug-free alternative for managing pain. Doctors routinely recommend TENS therapy because it is a low-risk, noninvasive type of treatment. The unit applies electrical muscle stimulation transcutaneously across a painful area. Here’s what you should know.

TENS unit devices, or TENS machines, look like a small cell phone. They have one or two sets of wire leads attached. The wire leads have a set of self-adhering pads attached to them. This device generates a gentle electrical current that travels through the lead wires to the pads on the body. The therapy works to decrease your pain levels by electrically stimulating the local sensory fibers. This can override the brain’s ability to process the pain signals from that area. It doesn’t make your muscles contract to do so.

Think of it like this. When you rub your knee when you hit it against something it helps reduce your pain. The rubbing sensation somewhat overrides the pain sensation and provides mild pain relief. Electrical stimulation was actually first used in ancient Rome to relieve pain by using electrical fish from the sea. Later, a variety of other devices were used to treat headaches and other pain conditions.

A TENS device is a safe option for many. However, if you have a pacemaker or are pregnant, you should avoid this type of therapy.

How Does TENS Unit Therapy Work?

Typically, a TENS device is a battery operated device. It introduces electrical stimulation at a high frequency and with an intensity that will not trigger motor contractions. Your physician can adjust the pulse, frequency, and intensity for specific conditions.

Unfortunately, researchers don’t completely understand how or why they work. As far as they can tell, TENS therapy for pain is effective because the nerve stimulation essentially keeps the nerves excited and busy. This prevents them from processing other sensations, in this case, pain. TENS therapy also encourages the production of endorphins, known to be the body’s natural painkillers. Although primarily used for pain control, this type of electrical stimulation has also been demonstrated to improve circulation locally. It can also either reduce or completely eliminate muscle spasms.

You’ll start treatment by placing the TENS electrodes on your skin where you’re experiencing pain. These electrodes connect to a small unit that generates electrical stimulation. The unit may produce a tingling sensation where the electrodes are placed on the skin. However, generally there are very few other side effects from therapy.