TENS (transcutaneous electrical nerve stimulation) is a treatment in which weak, low-frequency electrical pulses, usually in the range of 1 to about 150 Hz, flow through electrodes stuck to the skin. They stimulate the sensory nerves and inhibit the transmission of pain signals. TENS relieves pain symptomatically, mainly during and shortly after the treatment, but it does not remove the cause.
Below: how it works, types of TENS, indications, what the research says and contraindications.
In brief
- TENS relieves pain by stimulating the sensory nerves; typical frequencies are about 1–150 Hz.
- A meta-analysis of 381 studies (2022) found less pain during and immediately after treatment compared with placebo; evidence of a long-term effect is weak.
- The most important contraindications: a pacemaker, pregnancy (abdomen and pelvis), a cancerous lesion.
- A TENS session at the “W zdrowym ciele” clinic in Rydułtowy costs PLN 15.
- The clinic sees patients privately only (not covered by NFZ, the Polish public health fund), Mon–Fri 7:00–20:00.
Contents
How does TENS work on pain?
TENS works mainly in two ways. Higher-frequency pulses stimulate large sensory fibres which, in the spinal cord, “close the gate” to pain signals. Low-frequency pulses may also stimulate the release of endorphins, the body’s natural painkillers. In both cases the effect is symptomatic: the feeling of pain is reduced, not its cause.
The first mechanism is described by the gate control theory (Melzack and Wall, 1965): a sensory stimulus, such as the tingling from the current, “competes” with the pain signal in the spinal cord. That is why in physiotherapy TENS is part of a wider plan – it is meant to make exercise and manual therapy easier, as these are what actually improve function.
What types of TENS are there?
Three types of TENS are most commonly used in physiotherapy. Conventional TENS has a high frequency and low intensity and causes tingling without muscle contraction. Acupuncture-like TENS has a low frequency and higher intensity and may cause visible rhythmic muscle twitching. Burst TENS combines features of both. The physiotherapist chooses the settings according to the type of pain and the patient’s tolerance.
| Type | Frequency (approximate) | Sensation | Main mechanism |
|---|---|---|---|
| Conventional TENS | approx. 80–120 Hz | clear, comfortable tingling | pain inhibition in the spinal cord |
| Acupuncture-like TENS | approx. 1–10 Hz | tingling and rhythmic muscle contractions | release of endorphins |
| Burst TENS | bursts of high-frequency pulses repeated several times per second | pulsing tingling, slight contractions | mixed |
Approximate settings. Other types of current are described in our post electrotherapy — types of current.
What conditions is TENS used for?
TENS is used symptomatically for acute and chronic pain: back pain, shoulder and knee pain due to degenerative changes, nerve pain, muscle pain, pain after injuries and operations, and also labour pain. It works best as an addition to exercise, when pain makes it difficult to move and get back to everyday activities.
For back pain, TENS can be one element of therapy, but not its foundation – more on this in our guide to back pain. With nerve pain, e.g. after shingles, the skin may have altered sensation, so the electrodes are placed next to the painful area.
What does research say about how well TENS works?
The research results are mixed. A large 2022 meta-analysis of 381 studies found that during and immediately after treatment pain is lower than with a sham treatment, with moderate certainty of evidence. However, there is a lack of strong data on a long-term effect, and some guidelines, such as the UK NICE guideline on low back pain, do not recommend TENS.
A 2019 Cochrane overview of reviews concluded that the effectiveness of TENS for chronic pain cannot be clearly assessed, because the studies were small and varied. The takeaway for patients: TENS may give short-term relief and make exercise easier, but on its own it will not solve the problem of chronic pain.
Who should not have TENS?
TENS is not used in people with a pacemaker or an implantable cardioverter-defibrillator, over the abdomen and pelvis during pregnancy, on the front of the neck, on the eyes or on damaged skin, over a cancerous lesion, over an area of thrombosis, in people with impaired sensation, or around the head and neck in people with epilepsy.
Caution is also needed with other implanted electronic devices (insulin pump, neurostimulator, cochlear implant), heart rhythm disorders, allergy to the electrodes or gel, and situations in which the patient cannot report what they feel. This list is for general information, and the physiotherapist decides on eligibility after taking a history. A full overview for all treatments can be found in our post contraindications to physical therapy modalities.
What happens during a TENS session at the clinic?
Before the treatment, the physiotherapist asks about illnesses, medicines and implanted devices and checks skin sensation. They then attach two or four electrodes around the painful area or along the course of a nerve and gradually increase the intensity to a clear but comfortable tingling. The patient lies or sits, and can return to normal activities straight after the treatment.
The skin where the electrodes go should be clean, without creams or ointments. After the electrodes are removed, the skin may be slightly red, which usually fades quickly. The physiotherapist decides on the number and frequency of sessions individually after the consultation.
TENSsymptomatic relief of back, joint, muscle and nerve pain, once contraindications have been ruled outPLN 15Prices valid from 08.2026.
When should you see a doctor about pain first?
TENS relieves pain, but it can mask symptoms that need to be investigated. See a doctor first if you have pain after an injury or fall, night pain with unintentional weight loss, fever, sudden weakness of an arm or leg, numbness in the groin area, problems passing urine or stools, or chest pain.
Chest pain with shortness of breath or sweating needs urgent help (112). This list of red flags is for general information. Specialists the clinic works with are listed on the Recommended specialists page.
Good to know: before the treatment, tell the physiotherapist about a pacemaker, pregnancy and any implanted devices.
Summary
TENS reduces the feeling of pain mainly during and immediately after the treatment; a long-term effect is not well documented, so the treatment complements exercise. At the clinic in Rydułtowy a session costs PLN 15.
Frequently asked questions
Does TENS hurt?
TENS should not hurt. The patient feels tingling, buzzing or gentle tapping under the electrodes, and with acupuncture-like TENS also rhythmic muscle twitching. The intensity is set to a level that is clearly felt but comfortable. Burning, stinging or unpleasant heat under an electrode is a sign to tell the physiotherapist straight away.
Can TENS be used during pregnancy?
During pregnancy, electrodes are not placed on the abdomen, the pelvic area or the lower back, except when TENS is used for labour pain under the care of a midwife or doctor. For other areas of the body the decision is made individually, ideally after talking to the doctor looking after the pregnancy. Always tell the physiotherapist you are pregnant before the treatment.
Is it worth buying a TENS unit for home use?
A home TENS unit may be helpful for chronic pain when treatments at the clinic brought relief but the pain keeps coming back. Before buying one, it is worth discussing contraindications, electrode placement and settings with a physiotherapist. The unit does not replace exercise or diagnosis, and new or changing pain needs to be assessed by a specialist.
How many TENS sessions are needed?
The number of TENS sessions depends on the type and severity of the pain, its cause and how you respond to the first sessions. The physiotherapist decides this individually after the consultation and usually combines TENS with exercise or manual therapy. If there is no improvement despite the treatment, it is better to change the approach rather than continue with the same treatment.
Do I need a referral for TENS?
For a private treatment at the “W zdrowym ciele” clinic in Rydułtowy, a referral is usually not required. The clinic has no contract with the NFZ (the Polish public health fund), and a TENS session costs PLN 15. If you have a referral or recommendations from a doctor, bring them to your visit together with your test results, as they help in choosing treatments.
Can TENS be combined with other treatments?
Yes, TENS is often combined with exercise, manual therapy, kinesio taping or other physical therapy modalities such as magnetic field therapy. Reducing pain then makes it easier to do the exercises. The physiotherapist chooses the combination and order of treatments individually, checking contraindications for each of them separately, not just for TENS.
Sources
- Melzack R., Wall P.D., Pain mechanisms: a new theory, Science, 1965.
- Johnson M.I. et al., Efficacy and safety of transcutaneous electrical nerve stimulation (TENS) for acute and chronic pain in adults: a systematic review and meta-analysis of 381 studies (the meta-TENS study), BMJ Open, 2022.
- Gibson W. et al., Transcutaneous electrical nerve stimulation (TENS) for chronic pain – an overview of Cochrane Reviews, Cochrane Database of Systematic Reviews, 2019.
- NICE, Low back pain and sciatica in over 16s: assessment and management (NG59), 2016.
About the author: Tatiana Grabowska, MSc – master’s degree in physiotherapy, licence to practise number PWZFz 11646 (Polish physiotherapist licence). Since 2013 she has run the “W zdrowym ciele” physiotherapy and rehabilitation clinic in Rydułtowy; she has about 12 years of professional experience. Physiotherapist’s profile
- Consultation180 PLN
- Referralnot needed
- ReceptionMon–Fri: 7.00–20.00
