Alternate Title

  • Electroanalgesia

Related Terms

  • Related techniques: Acupuncture-like TENS, auricular TENS, CODETRON, electronic muscle stimulators, electroanalgesia, peripheral nerve stimulation, sensory afferent stimulation (SAS), TES (transcutaneous electrical stimulation), TNS (transcutaneous nerve stimulation), TNS (transcutaneous neural stimulation), TENMS, transcutaneous electrical analgesia.
  • Not included in this review: Cerebral TENS, cranial TENS, deep brain stimulation (DBS), epidural stimulation, percutaneous electrical stimulation (PENS), spinal cord stimulation (SCS), subcutaneous nerve stimulation (SCNS), or use of electrical stimulation for muscle toning.

Background

  • Transcutaneous electrical nerve stimulation (TENS) is a non-invasive technique in which a low-voltage electrical current is delivered through wires from a small power unit to electrodes located on the skin. Electrodes are temporarily attached with paste in various patterns, depending on the specific condition and treatment goals. TENS is often used to treat pain, as an alternative or addition to pain medications. Therapy sessions may last from minutes to hours.
  • TENS devices can be set in a wide range of frequencies and intensities, depending on patient preferences, desired sensations, and treatment goals. “Conventional TENS” involves the delivery of high or low frequency electrical current to affected areas. In “acupuncture-like TENS,” lower frequencies are used at specific “acupuncture points” or trigger points. TENS may also be applied to locations on the ear (“auricular points”). Epidural stimulation and percutaneous electrical nerve stimulation (PENS), which are not included in this review, are invasive procedures that require penetration of the skin, implantation, or minor surgery.
  • The practice of using electricity for pain control can be traced to 2500 BC and the Egyptian Fifth Dynasty, in which stone carvings depict an electric fish being used to treat pain. During the Socratic era, electrogenic torpedo fish (Scribonius longus) were used to treat arthritis and headache. In the Middle Ages, electrostatic generators were used, and the discovery of the electric battery in the 19th century led to further experimentation.
  • The use of electrical stimuli for pain relief was popularized in the 19th century and became widespread in the 1960s and 1970s using battery power.

Evidence Table

    Disclaimer

    These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

    Dental procedures

    Several small randomized controlled trials in adults and children report pain reduction or reduced need for pain medications during dental procedures with the use of various TENS techniques. These studies provide promising preliminary evidence but do not include clear descriptions of design or results. Therefore, better research is necessary before a strong recommendation can be made.

    Knee osteoarthritis

    Multiple randomized controlled trials have examined the effects of TENS in patients with osteoarthritis of the knee. Overall, the results suggest improvements in knee stiffness and pain, although it is not clear that walking distance or swelling are improved. The available studies have been small without clear descriptions of design or results. Therefore, better research is necessary before a strong recommendation can be made.

    Anesthesia (pain relief during surgery)

    Auricular TENS is sometimes used in Europe to reduce the need for anesthesia during surgical procedures. There is not enough reliable evidence to draw a firm conclusion in this area.

    Alzheimer’s disease

    Preliminary research suggests that TENS may benefit some symptoms of Alzheimer’s disease, including mood, memory, and cycles of daily rest and activity. Additional human study is necessary before a firm conclusion can be drawn.

    Angina (chest pain)

    Several small, brief studies report benefits of TENS on angina pectoris pain. However, most studies were conducted during the late 1980s and early 1990s, and were not well designed or reported. New drugs for heart disease have been developed since these studies were conducted, and people with heart disease or chest pain are advised to seek immediate medical attention from a licensed physician.

    Ankylosing spondylitis

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Back pain

    The effects of TENS or acupuncture-like TENS on low back pain remain controversial, and multiple controlled trials have been published in this area. Studies have not been consistent in the type of TENS techniques used (location, intensity, frequency, duration) or in definitions of back pain, and most trials have not been well designed or reported. Published meta-analyses have grouped some of these studies together to try to determine whether this technique is effective, but have also yielded inconsistent results, with some authors reporting overall benefits, and others finding no clear advantage over placebo. Better-designed research is needed before a firm conclusion can be reached.

    Burn pain

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Cancer pain

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Chronic pain

    The effect of TENS on chronic pain of various causes and locations remains controversial, and multiple controlled trials have been published in this area. Although numerous studies report benefits, studies have overall been small, poorly designed, and without clear descriptions of results. Better-designed research is needed before a firm conclusion can be reached.

    Dysmenorrhea (painful menstruation)

    TENS has been examined for the treatment of dysmenorrhea in several small studies. Research in this area suggests that the use of TENS may reduce short-term discomfort and need for pain medications. However, the available trials do not clearly describe study designs or results. Most outcomes are not measured using validated scales. Overall, blinding, randomization, dropouts, and statistical analysis are not well described. Sample sizes are small. Therefore, the research in this area remains indeterminate.

    Headache

    Preliminary controlled trials suggest that TENS may have some benefits in patients with migraine or chronic headache. Additional well-designed research is necessary before a firm conclusion can be reached in this area.

    Hemiplegia / hemiparesis

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Labor pain

    The effect of TENS on labor pain remains controversial, and multiple controlled trials have been published in this area. Although some research reports small benefits, including reduced need for pain medications, studies have overall been small, poorly designed, and without clear descriptions of results. Better-designed research is needed before a firm conclusion can be reached. It is not clear if passage of electricity using TENS has harmful effects on the fetus.

    Local anesthesia during gallstone lithotripsy

    TENS has been tested for its effects on pain control during lithotripsy (a technique used to break up gallstones). Currently, there is not enough reliable evidence to draw a firm conclusion in this area.

    Facial pain / trigeminal neuralgia

    Several studies report benefits of TENS in patients with chronic facial pain of various causes. However, these trials have been small without clear descriptions of design or results. Therefore, additional research is needed before a firm conclusion can be drawn in this area.

    Myofascial pain

    There is preliminary data that high frequency/high intensity TENS may benefit myofascial pain. However, currently there is insufficient evidence from well-designed controlled trials to support this use.

    Nausea/vomiting of pregnancy

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Neck and shoulder pain

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Pain from broken bones / acute trauma

    There is not enough reliable evidence to draw a firm conclusion in this area.

    Peripheral neuropathy

    Several case reports and a small number of controlled trials report improvements in pain symptoms in people with peripheral neuropathy or nerve damage. However, these studies have not been well designed or reported, and additional research is needed before a firm conclusion can be drawn about effectiveness.

    Phantom limb pain

    There is not enough reliable evidence to draw a firm conclusion in this area. Promising preliminary research requires confirmation with better quality studies.

    Post-herpetic neuralgia

    TENS has been used in post-herpetic neuralgia, however there is insufficient evidence from controlled clinical trials upon which to base recommendations.

    Post-operative ileus

    There is conflicting evidence from clinical trials on the effectiveness of TENS in post-operative ileus. Well-designed, large studies are needed before a recommendation can be made.

    Post-operative nausea / vomiting

    There is not enough reliable scientific evidence to firmly conclude if TENS is beneficial in patients with pain after surgery.

    Post-operative pain

    There are multiple controlled studies of TENS for pain following various types of surgery, including abdominal surgery, heart surgery, lung surgery, gynecologic surgery, and orthopedic surgery.

    Research is inconsistent, with a variety of TENS techniques, patient types, and study designs used. Overall, the quality of available research is poor. Although some studies do report improvements in pain and reduced need for pain medications, a well-designed review in 1996 concluded that there is no clear evidence of benefit. Better quality research is necessary in this area before a strong conclusion can be reached.

    Post-stroke rehabilitation

    Studies of TENS in post-stroke rehabilitation report inconsistent findings, and benefits have not consistently been demonstrated. Additional research is necessary before a clear conclusion can be reached.

    Rheumatoid arthritis

    Preliminary studies of TENS in rheumatoid arthritis report improvements in joint function and pain. However, most research is not well designed or reported, and better studies are necessary before a clear conclusion can be reached.

    Skin flap ischemia

    TENS has been tested for its effects on blood flow to skin flaps used in plastic surgery procedures such as breast reconstruction. Currently, there is not enough reliable evidence to draw a firm conclusion in this area.

    Skin ulcer

    TENS has been evaluated in patients with diabetic foot ulcers and chronic ulcers of other causes. There is not enough reliable evidence to draw a firm conclusion in this area.

    Spinal cord injury

    There have been limited non-controlled trials of TENS in spinal cord injury. Well-designed controlled trials are required to recommend for or against the use of TENS for this indication.

    Temporomandibular joint pain (TMJ)

    There is insufficient reliable evidence to recommend for or against the use of TENS in temporomandibular joint pain.

    Urinary incontinence / detrusor instability

    There is not enough reliable evidence to draw a firm conclusion in this area.

*Key to grades:

Tradition

    Disclaimer

    The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Safety

    Disclaimer

    Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.

Attribution

  • This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().

Bibliography

    Disclaimer

    Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.

  • Brosseau L, Milne S, Robinson V, et al. Efficacy of the transcutaneous electrical nerve stimulation for the treatment of chronic low back pain: a meta-analysis. Spine 2002;27(6):596-603.
    View Abstract
  • Carroll D, Moore RA, McQuay HJ, et al. Transcutaneous electrical nerve stimulation (tens) for chronic pain (Cochrane review). Cochrane Database of Systemic Reviews 2001;(4.)
    View Abstract
  • Chandran P, Sluka KA. Development of opioid tolerance with repeated transcutaneous electrical nerve stimulation administration. Pain 2003;102(1-2):195-201.
    View Abstract
  • Gadsby G, Flowerdew M. Nerve stimulation for low back pain–a review. Nurs Stand 1997;11(43):32-33.
    View Abstract
  • Ghoname EA, White PF, Ahmed HE, et al. Percutaneous electrical nerve stimulation: an alternative to TENS in the management of sciatica. Pain 1999;83(2):193-199.
    View Abstract
  • Hsieh RL, Lee WC. One-shot percutaneous electrical nerve stimulation vs. transcutaneous electrical nerve stimulation for low back pain: comparison of therapeutic effects. Am J Phys Med Rehabil 2002;81(11):838-843.
    View Abstract
  • Johansson BB, Haker E, von Arbin M, et al. Acupuncture and transcutaneous nerve stimulation in stroke rehabilitation: a randomized, controlled trial. Stroke 2001;32(3):707-713.
  • Mannheimer C, Carlsson CA, Vedin A, et al. Transcutaneous electrical nerve stimulation (TENS) in angina pectoris. Pain 1986;26(3):291-300.
    View Abstract
  • Milne S, Welch V, Brosseau L, et al. Transcutaneous electrical nerve stimulation (TENS) for chronic low back pain (Cochrane Review). Cochrane Database Syst Rev 2001;2:CD003008.
    View Abstract
  • Munhoz RP, Hanajima R, Ashby P, et al. Acute effect of transcutaneous electrical nerve stimulation on tremor. Mov Disord 2003;18(2):191-194.
    View Abstract
  • Osiri M, Welch V, V, Brosseau L, et al. Transcutaneous electrical nerve stimulation for knee osteoarthritis (Cochrane Review). Cochrane Database Syst Rev 2000;4:CD002823.
    View Abstract
  • Peters EJ, Lavery LA, Armstrong DG, et al. Electric stimulation as an adjunct to heal diabetic foot ulcers: a randomized clinical trial. Arch Phys Med Rehabil 2001;82(6):721-725.
    View Abstract
  • Price CIM, Pandyan AD. Electrical stimulation for preventing and treating post-stroke shoulder pain (Cochrane review). Cochrane Database of Systemic Reviews 2001;(4):CD001698.
    View Abstract
  • Proctor ML, Smith CA, Farquhar CM, et al. Transcutaneous electrical nerve stimulation and acupuncture for primary dysmenorrhoea. Cochrane Database Syst Rev (last updated 2002-02-28) 2002;(4):CD002123.
    View Abstract
  • Zarate E, Mingus M, White PF, et al. The use of transcutaneous acupoint electrical stimulation for preventing nausea and vomiting after laparoscopic surgery. Anesth Analg 2001;92(3):629-635.
    View Abstract