What is TENS?

TENS (Transcutaneous Electrical Nerve Stimulation) is a drug-free therapy designed to manage pain using electrical nerve stimulation through a TENS unit (a small, portable, battery-powered device). For over 40 years, doctors have been prescribing TENS as an effective way to relieve pain. The TENS device is the most effective treatment for pain relief, by reducing and often eliminating pain, offering a better quality of life. It is FDA approved, and is reimbursable by most insurance providers.

TENS therapy is used for many conditions, including Bursitis, Arthritis, Cancer, MS, Tendonitis, Diverticulosis, Surgery, Knee/back/ankle etc. pain, Sciatica, Migraines, Menstrual pain, Labor pain, and Headaches. It is also frequently used for injuries and wounds.

How TENS Works

TENS was designed to relieve pain by sending gentle impulses through the skin to the nerve endings. For proper TENS treatment for pain, electrodes should be strategically placed at appropriate pain sites on the body. The TENS unit will send gentle electrical impulses through lead wires to the electrodes which transmits them through the skin to the nerve fibers, creating a tingling or massaging sensation. This suppresses pain by blocking the pain signals before they reach the brain.

TENS is believed to work by two different mechanisms. First, electrical stimulation of the nerve fibers can block a pain signal from being carried to the brain. If the signal is blocked, pain is not perceived. Secondly, the body has its own mechanism for suppressing pain. It does this by releasing natural chemicals called endorphins in the brain, which act as analgesics. The TENS unit provides several different modes of operation, equipping the user with a variety of treatment options. Most units offer two channels, so it can be used to relieve pain at two different body locations. TENS units have different adjustable settings to control amplitude (intensity) of stimulation by controlling the voltage, current, and pulse width (duration) of each pulse. The TENS is about the size of a deck of playing cards, so you can wear it anywhere, at home, to work, or even in your car. A convenient belt clip allows you to wear it on your belt or even inside your clothing.

The Theory Behind TENS

Its use dates back to the 1960s with the introduction of the “Gate Control Theory” of pain, and it remains the most respected theory of pain perception. According to the theory, stimulating nerves closes a "gate" mechanism in the spinal cord, and that can help eliminate the sensation of pain.

It was discovered that pain impulses could be overridden and the perception of pain could be altered. Pain is an emotional experience encompassing neurobiological mechanisms. It is a very unique, personal experience and highly influenced by circumstances and interpretation. Pain occurs when specialized nerve receptors are stimulated and messages are passed from the nervous system to the brain, where they are interpreted as pain. Basically, the brain can only cope with a certain amount of information at once. For unknown reasons, probably linked to survival, sensation impulses from the nerves have priority over pain signals. When a TENS unit is used, you feel it strongly, and the pain subsides.

Another theory is that stimulating the nerves may help the body produce natural painkillers called endorphins. This is called the “Endorphin Release Theory”. TENS stimulates endorphin release (the body’s natural painkillers) to help reduce pain. Endorphins (or 'endogenous opiates') were first discovered in 1975. They are natural opiate-like substances, similar to morphine, but not as potent and without the side effects. Endorphins are manufactured by our bodies in response to pain and act as a natural pain killer. Endorphins are released by the descending nerve fibers or nerves which travel down the spinal cord from the brain. When we feel pain, the descending nerve fibers release endorphins at the spinal cord, where they meet the sensory nerves carrying the 'pain messages' from our body. This local release of endorphins by the nerves inhibits some or all of the pain messages going up to the brain. For many women, endorphins will also positively alter the memory of their birth experience and in some cases cause her to forget the pain. Endorphins can therefore empower women and provide a positive memory and experience associated with labor and birth.

How to Use a TENS Unit

1. Make sure that the battery is properly inserted in the unit. The TENS unit has 2 control knobs. Each control knob controls the strength of the electrical signals for each channel. There may be additional controls that adjust the wave length, impulse frequency and treatment time. Turn the control knobs to the off position before you start.
2. Use alcohol to clean the skin where the electrodes will be placed. Wait till your skin is dry.
3. Most of today’s electrodes are already pre-gelled, so you can just attach them to your lead wires and placed then near the area where you experience pain.
4. Connect the pin connectors on the end of the electrode wires to the electrodes. Then plug the other end of the lead wires into the TENS unit.
5. Turn the control knobs slowly to the correct setting. You should feel a tingling sensation.
6. Secure your TENS unit to your belt or place it in a pocket.

What should I do after the TENS treatment?

1. Turn the control knobs to the off position. Unplug the electrode wires from the TENS unit.
2. The electrodes should be removed after treatment and placed back on the liner that they were originally packaged on. To prolong the life of electrodes, they should be stored in a cool area. Wash the skin where the electrodes were placed. Replace electrodes if they become damaged, or loose the adhesion and will not adhere to the skin. A body lotion with Aloe can be applied to the skin, after the treatment.

Does TENS Treatment have any risks or side effects?

Unlike surgery or prescription drugs, TENS is virtually risk free from injury, side effects or addiction.  The low-volt electrical current delivered by the electrodes only penetrates the skin to the level of the nerve fibers, usually only one to two inches.  This poses no danger to most individuals.  However, those with cardiac conditions and/or pacemakers, and pregnant women should consult their doctors before using TENS.  Also, neck and head pain that requires locating electrodes on these areas of the body should be conducted only with the consent of a physician.  Use caution when you drive or operate heavy machinery.