The exact mechanism of electrical stimulation’s beneficial effect remains controversial. Electrical stimulation may directly block transmission of pain signals along nerves. In addition, electrical stimulation has been shown to promote the release of endorphins, which are natural painkillers produced by the body.
TENS, IFC, and GS all apply electrical stimulation to nerves and muscles via adhesive pads placed on the skin. These devices are powered by batteries, and some units have an adapter that allows powering from an outlet.
Side effects are rare, but include allergic skin irritation under the adhesive pads and transient pain from the electrical charge. Placing the pads over the heart or over pacemaker leads could conceivably cause cardiac arrhythmia; placing them over the throat could conceivably cause low blood pressure; and placing them over a pregnant uterus could conceivably cause fetal damage. Because of these risks, electrical stimulation over these areas should be avoided. Electrical stimulation should also not be applied over malignancies or infected areas.
Proof of licensee is required for all items under this category.