Tens Side Effects


Tens, or transcutaneous electrical nerve stimulation, is a technique used by a number of health care providers in which a patient is attached to a machine with electric currents in an attempt to relieve pain. Several electrodes are attached with gel or tape and mild electric currents are sent through the electrodes.

Tens has a number of advantages, including that the machine is passive and non-invasive. Unlike surgical procedures or medications, the tens unit is not addictive and it works it to improve mobility, decrease pain perception and has been successfully used to control acute and chronic pain.
No medication or medical device is entirely without risk and the tens unit is no exception. Depending on the machine and its power, there are several potential side effects, including skin irritation and redness, and in rare cases, can cause hives, welts, allergic skin reactions, and even burns.

It is critical when beginning to use the tens unit to do so under the guidance of a trained health care provider. A number of isolated side effects such as nausea, muscle ache, headache, increased hair growth, dizziness, and loss of sensation have been reported after using the tens.

According to the Merck Manual, it is recommended that the tens unit be used from a minimum of 20 minutes up to a several hour period. The tens unit should not be used for significant periods of time if the patient becomes uncomfortable or the muscles become sore. Muscle twitching is an indication that overstimulation has occurred.

As always, when beginning any new medical treatment, including tens, speak with your health care provider about the specific risks you might encounter. Make sure you use a tens unit that has been certified for use by the Food and Drug Administration.


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