What Is TENS?
TENS, or transcutaneous electrical nerve stimulation, is a pain relief method that uses mild electrical currents to block pain signals or change how you perceive them. It's used for back pain and for pain associated with conditions such as osteoarthritis and fibromyalgia.
TENS is typically done with a TENS unit, a small battery-operated device. Some TENS devices are used in medical clinics, while others are used at home. The devices have wires connected to sticky pads called electrodes. The pads go on your skin in the area that hurts. When the machine is turned on, the electrodes carry low-voltage electric currents from the TENS machine to your body.
Despite 50 years of research, scientists still aren't sure how — or even if — TENS really works. While doctors and patients often report that pain eases during treatment, patients differ on whether there are any lasting effects.
If TENS does work, it may be because the electrical currents stimulate nerve cells that block pain signals. Or the treatment may trigger your body to release pain-killing chemicals called endorphins.
TENS For Back Pain
When you get TENS for back pain, electrodes are placed on the skin over the area of your back that hurts. When the machine is turned on, you feel a tingling sensation. If TENS works for you, you can expect to feel immediate pain relief. Your pain might come back shortly after treatment, but some people report relief for up to 24 hours.
TENS for lower back pain
Research has for the most part failed to support the use of TENS as a stand-alone treatment option for lower back pain. One review of four studies comparing real TENS treatments to placebo versions (usually using TENS-like devices without electricity) found conflicting evidence on whether TENS was any better than the fake treatments at making lower back pain less intense.
Some guidelines for the treatment of chronic lower back pain — pain that doesn't go away after 3 months — say TENS is worth trying for some people. It's considered an alternative treatment that might help when exercise, medication, or other standard treatments aren't enough. Acupuncture, massage, and biofeedback are other examples of alternative treatments for lower back pain.
How to Use TENS
TENS, when properly used, either in a medical clinic or at home, is generally safe. But it's not for everyone.
Who should not use a TENS unit
If you think you would like to try TENS for back pain, speak to your doctor. Your doctor may advise against using TENS if you are pregnant, especially in the early weeks of pregnancy, or if you have:
- A pacemaker or other electrical or metal implant in your body
- Epilepsy (a seizure disorder)
- Cancer
- Deep vein thrombosis (a blood clot)
- A bleeding disorder
- Heart disease
TENS placement for lower back pain
If you are placing your own TENS pads, make sure you follow instructions from your doctor or physical therapist, even if you are trying a unit you bought on your own.
You should also refer to instructions that come with your device.
Typically, for lower back pain, you might be advised to:
- Place pads on either side of the most painful area or above and below it
- Always use at least two pads because one alone won't work (some units come with two pads, others with four)
- Make sure the pads don't touch and are at least an inch apart
- Avoid placing pads directly over your spine
TENS at home
When you use a TENS unit at home for your back pain, make sure the skin in the area you want to treat is clean and dry, with no lotion or other skin products on it.
Once the pads are in place, you can turn on the machine at a low setting. You'll feel a slight tingling sensation. The machine will have a dial that you can use to adjust the strength of the electrical impulses. You can raise the intensity until you reach a level of tingling that feels strong but still comfortable.
Research suggests you'll get the most out of TENS if you use it while you're active. It's less likely to help if you use it while sitting or lying down. Your unit may come with a carrying pouch or a clip to attach to a belt, so it's easy to use while moving.
Take these precautions when using TENS at home:
- Use TENS only for the reason OK'd by your doctor or physical therapist.
- Let your doctor or therapist know if your condition changes.
- Do not leave electrodes in place for long periods without checking and cleaning the skin beneath them.
- If a rash or burn develops beneath the electrodes and lasts more than 6 hours, stop TENS and call your doctor or physical therapist.
- Don't place electrodes on broken or irritated skin.
- Don't drive while using a TENS unit.
- Don't use the device in the shower or bathtub.
- Don't use a TENS unit with heating pads or cold packs.
- Don't use TENS while sleeping.
TENS Side Effects
While TENS is generally safe, some people have side effects such as:
- Allergic reactions to the adhesives on the pads
- Unpleasant sensations (if you don't like the tingling, prickling feeling produced by TENS)
- Burns, in rare cases
- Headaches
- Dizziness
- Nausea
If you have any of these problems, stop using TENS and get in touch with your doctor.
Takeaways
If you have chronic back pain and aren't getting enough relief from standard treatments like exercise and medication, TENS might be worth trying. It's generally safe, and some people say it works for them — though there's no firm research proving it makes a significant difference. If you want to try TENS, talk to your doctor or physical therapist first.
TENS for Back Pain FAQs
How often should you use a TENS unit for back pain?
It's generally OK to use it as often as you like. Some people use it several times a day for up to an hour at a time. But check with your doctor or physical therapist.
What are the disadvantages of TENS therapy?
While some people have side effects, such as allergic reactions to the sticky pads, TENS is quite safe for most people. One disadvantage of any alternative therapy is that you might spend time and money on something that doesn't work as well as proven therapies.
Where should you not put TENS pads?
In addition to avoiding irritated or broken skin, you should avoid putting pads on the side of your neck, anywhere on your face or head, on numb skin, or over any varicose veins. Also, never put pads on your chest and upper back at the same time.
