TENS is a method of pain relief for people with chronic pain or women in labour. A TENS machine delivers a small electrical current to the body through electrodes attached to the skin. It does not involve medicines or injections.

What is TENS?

TENS stands for transcutaneous electrical nerve stimulation. Transcutaneous means across the skin. TENS is also called electrotherapy.

A TENS machine passes electricity across the skin to stimulate the nerves and relieve pain.

A TENS machine runs on batteries. Small electrodes are put on the skin, and the electrodes are connected to the TENS machine. The machine sends pulses of gentle electric current to the electrodes. The current stimulates the nerves near the pain.

Some people find it gives some pain relief. It uses no medicines, no needles and no injections.

But it isn't clear how it works. It's possible that it blocks pain signals by stimulating different nerves in the spinal cord. TENS might also cause the release of endorphins — the body's natural pain relievers.

Medical uses for TENS

TENS can give pain relief in labour. It is also used for chronic pain in people who have conditions such as cancer or arthritis. Physiotherapists sometime use it to treat muscle pain.

Is TENS effective?

TENS helps ease pain for some people, but not for others.

Risks and safety

TENS is thought to be safe. But it should not be used:

• on an open wound
• if your skin is irritated
• near sensitive areas such as your eyes
• while driving or operating machinery
• in or around water

It should not be used by:

• women who are pregnant but not in labour
• people with a pacemaker or a cochlear implant
• people with epilepsy

TENS shouldn't be painful, but some people find it uncomfortable. Some people find skin irritation where the electrodes are attached.

How to get a TENS machine

You might be able to rent or borrow a TENS machine from a physiotherapist or a hospital.

You can buy your own, but you should ask a physiotherapist or health professional for advice on the settings that are best suited for your problem.