TENS unit side effects, cautions and warnings

There are virtually no TENS unit side effects. At most, skin irritation, a very rare allergic reaction to gel and electrode burns are possible. Should any occur, stop using the device and notify your doctor. However, the absence of adverse events that does not mean safety information, such as the following, should be neglected.


·         TENS units are restricted to sale by or on the order of a doctor by United States federal law.

·         Do not use for undiagnosed pain syndromes without consulting a doctor.

·         People with cardiac pacemakers, implanted defibrillators, or any other implanted metallic or electronic device should consult a doctor before using a TENS device

·         The same applies to patients with heart disease, epilepsy, cancer, or any other medical condition.

·         Stimulation may be enough to cause electrocution. Electrical current of such magnitude should not flow through the thorax or across the chest as it could result in cardiac arrhythmia.

·         Do not apply electrodes to the front of the throat lest spasm of the laryngeal or pharyngeal muscle occurs. Stimulation of the carotid sinus may close the airways, leading to breathing difficulties and potential TENS unit side effects on the heart rhythm or blood pressure.

·         Do not apply electrodes to the head or any site where electrical current may flow transcerebrally.

·         Do not use a TENS machine while driving, operating machinery, close to water, or during any activity where involuntary muscle contractions may endanger the user.

·         Turn unit off before attaching or removing electrode pads.

·         If therapy becomes uncomfortable or fruitless, treatment should be stopped until reassessed by a doctor.

·         Keep TENS units away from children.

·         Do not use around explosive atmosphere and flammable mixture.


·         Use TENS devices only under the constant supervision of a doctor.

·         TENS treatment has no curative value.

·         TENS is a symptomatic therapy that suppresses pain sensation that otherwise serves as a mechanism of protection.

·         Not effective for pain of central origin, including headaches.

·         ECG monitors and alarms and other electronic monitoring supplies may not work properly during TENS stimulation.

·         Do not apply electrodes over the eyes, in the mouth, or internally.

·         Do not use during sleep.

·         Do not use while pregnant unless prescribed by a doctor.

Bear in mind that another potential side effect is pain; this usually stems from using the TENS unit for overly long periods or at too high an intensity. Ask your doctor about the frequency, duration, and intensity of treatment that better suit your case.

Related Read:

Electrotherapy Side Effects: TENS 7000 vs. Pain Medication