---
title: "What Is TENS unit? TENS and Pain Glossary | Analgesic Healthcare"
description: "A TENS unit is a small, battery-powered device with wires and electrode pads that sends mild electrical pulses through the skin to relieve pain, used as your..."
url: https://analgesic.multisites.ai/glossary/tens-unit
publisher: Analgesic Healthcare
phone: +1-800-749-1188
contact: https://analgesic.multisites.ai/contact
---

Device

# TENS unit

A TENS unit is a small, battery-powered device with wires and electrode pads that sends mild electrical pulses through the skin to relieve pain, used as your clinician and the device instructions direct.

The NHS describes a TENS machine as a small, portable device with a battery and wires with sticky pads that you put on your skin. This site uses the term TENS unit for the same device. The unit makes the electrical pulses. The [lead wires](https://analgesic.multisites.ai/glossary/lead-wire) carry them to the [electrode pads](https://analgesic.multisites.ai/glossary/electrode-pad). The unit has controls that set the current, and the NHS advises turning the dial slowly until you feel a tingling sensation that is not painful. The NHS says you can buy a TENS machine online or in shops, and a prescription device must carry an "Rx only" label under 21 CFR 801.109, so check your model's label. Follow your clinician's and your device's instructions. Read [TENS unit safety](https://analgesic.multisites.ai/guides/tens-unit-safety) before you start.

## Related terms

-   [TENS](https://analgesic.multisites.ai/glossary/tens)
-   [Electrode pad](https://analgesic.multisites.ai/glossary/electrode-pad)
-   [Lead wire](https://analgesic.multisites.ai/glossary/lead-wire)
-   [Stimulation intensity](https://analgesic.multisites.ai/glossary/stimulation-intensity)

## Sources

1.  [NHS: TENS (transcutaneous electrical nerve stimulation)](https://www.nhs.uk/conditions/transcutaneous-electrical-nerve-stimulation-tens/)
2.  [eCFR: 21 CFR 801.109 Prescription devices](https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-801/subpart-D/section-801.109)

## Questions about your unit or a bill?

Call toll free. For customer care, ask for extension 508.

[Call (800) 749-1188](tel:+1-800-749-1188)[Pay invoice](https://ahcpatientservices.com/)