TENS machine side effects

What are the TENS machine side effects?

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What are the TENS machine side effects? Are there any TENS unit benefits? Do they really work to relieve from pain? How to use a TENS Unit? A TENS or Transcutaneous Electrical Nerve Stimulation (TENS) unit is a battery-operated device that some people use to treat pain. TENS unit works by delivering small electrical impulses through electrodes that have adhesive pads to attach them to a person’s skin. These electrical impulses flood the nervous system, reducing its ability to transmit pain signals to the spinal cord and brain. The same electrical impulses also stimulate the body to produce natural pain relievers called endorphins. Are there any TENS machine side effects?

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TENS machine side effects

What is a TENS machine (Unit)?

Transcutaneous Electrical Nerve Stimulation (TENS) or TENS Unit is a treatment that administers mild electrical currents to the skin to relieve pain. A small, lightweight, hand-held, battery-operated device produces the electrical currents and lead wires send these currents to self-adhesive electrode pads that attach to your skin.

While using a TENS machine, you’ll experience a non-painful tingling or buzzing sensation, and this can help to block or suppress pain messages. Two electrode pads are usually positioned either side of the area of most intense pain. This is done so that the TENS sensation covers the painful area.

Four electrode pads can be used to treat a larger area of pain. You’ll be able to control the strength, (or ‘volume’) of the current that’s passed through the electrodes, with a rotary knob or dial. Some machines have larger controls that are easier to use if your hand movements are limited.

Adjust the strength of the current until the tingling sensation from TENS is strong, but not painful. You’ll also be able to adjust the pattern and speed of the current, so that the TENS sensation is as comfortable as possible. Many TENS machines are digital and have helpful pre-sets to help you choose the best settings for your pain.

What are the TENS machine side effects?

TENS machine has minimal side effects if the following precautions are followed:

  • Check with your doctor or physiotherapist to make sure that using a TENS machine is a safe option for you. 
  • Don’t use a TENS machine if you have a pacemaker or other implanted electrical device. You should check with your physiotherapist that TENS is a safe option for your pain if you have epilepsy, deep vein thrombosis (DVT), heart problems, cancer or skin that is numb, irritated or fragile. 
  • TENS can be used if you have these conditions, but you must seek advice from your physiotherapist or doctor first. 
  • Generally, you can use TENS during early pregnancy, providing it isn’t used over the abdomen or lower back. Again, you must check with your physiotherapist or doctor that TENS is a safe option for your situation. 
  • Never place the electrodes over the front of your neck, over your eyes, directly on your head or in your mouth. 
  • Don’t use TENS when driving, using machinery, sleeping, or in the bath/shower. 
  • Your skin may become slightly red and itchy when you remove the electrodes, but this should disappear quickly. It’s important to monitor your skin regularly after using TENS, to ensure it remains healthy. 
  • If redness, itchiness and soreness persist, then contact your physiotherapist, GP or pharmacist for advice. Some people develop a more serious skin reaction to TENS and may need to temporarily stop using it to let the skin recover. 
  • If you intend to use TENS when flying, inform the airline first.

Since June 1998, TENS machines must be marked with a European stamp of safety (CE mark).

Are there any TENS machine side effects really? One of the reasons why TENS is so popular and reliable as a treatment option is that it comes with very few risks. Especially in comparison to pills, which have innumerable potential side effects, TENS is very safe. Still, users should take precautions. Here are 10 TENS Unit side effects to be aware of:

1. Unpleasant Electric Shocks to the Skin

If your skin is wet when applying your TENS unit, or if the pads are not applied correctly, you may feel unpleasant shocks. Be sure to dry your skin thoroughly and to read your unit’s manual to ensure proper adhesion.

As you can see, these TENS Unit side effects are mostly due to operator error or are minimal at worst. The safety and effectiveness of TENS is why it has become the most popular way to relieve pain.

2. Burn Marks

Most of the 10 side effects from TENS will come from either leaving on the electrode pads for too long or from setting the intensity level too high. However, most over-the-counter TENS units come with pre-set modes which help prevent users from making this mistake. If burn marks do occur as TENS machine side effects, avoid using your TENS machine until they have healed. Use aloe vera to provide relief.

3. Irritation in skin

Sometimes if electrode pads are left on for long periods of time without checking the skin, irritation can occur as TENS machine side effects. To avoid this, wash skin thoroughly before applying pads. Check skin underneath electrode pads every ten minutes making sure skin is not irritated.

4. Loss of Muscular Control

In almost all cases, TENS therapy can be applied throughout the day. The discrete, small machines can be placed underneath the shirt so that TENS can be applied during work, athletic activities or at home while relaxing. However, there is a small chance that while TENS is being applied, it will affect the way you feel and move your muscles. Because of this, do not drive a car or operate heavy machinery while using TENS.

5. Close to open wounds, damage may occur

If TENS unit pads are placed on or too close to open wounds or damaged skin, the wound can become further irritated as TENS machine side effects. The wound may also take longer to heal. Because of this, avoid placing electrode pads on or near damaged skin.

6. Potential Fetal Harm

TENS has not been tested to discover its effect on fetuses. Women who are pregnant should not use TENS near the uterus without first consulting their doctor.

7. Muscle Pain

Very few people find TENS therapy to be unpleasant. However, if you are one of the few who feel muscle pain while using TENS, chances are that you have the intensity set too high. Try a lower setting. You might also try moving the pads further apart.

8. Muscle Twitching

When a TENS unit is turned too high, muscle twitching can occur. If this happens, turn the machine down immediately until twitching ceases. Make sure your TENS unit is turned all the way down and starts from zero each time you put it on. Only increase the intensity to fit what feels right for you. Pain is as unique as the person who suffers from it, so not everyone will benefit from the same setting.

9. Muscle Soreness

Again, if you experience muscle soreness the day of or the day after TENS therapy as TENS machine side effects, it was probably caused by having the settings too high. Take a break from your TENS unit for a few days. When you return, be sure to start low, and only increase the intensity as you need it.

10. Facial Nerve Damage

This sounds, by far, like the most intimidating of the 10 side effects from TENS. However, the only case in which this is possible is if the TENS unit is placed on the face. It is never recommended by any manufacturer to place electrode pads on the face. To play it safe, steer clear of any area above the neck and around the throat, and you will not be in danger of this side effect.

What are TENS Unit Benefits?

TENS is a non-invasive method of pain relief. It can be used alone or in addition to prescriptions or over-the-counter pain-relieving medications. The amount of medication may be able to be reduced in some patients who use TENS therapy. Do not stop taking or make any adjustments in your dose of medications without discussing it with your doctor first.

Another benefit of the TENS unit is that it is small and portable and therefore can be used at home or away, anytime pain relief is needed.

TENS Unit Benefits

Pain Relief

The primary advantage of using a TENS machine is nerve stimulation to distract pain centers and thus reduce the feeling of chronic pain (TENS Unit Benefits). From back to arm pain, one can rely on a Tens unit to derive relief naturally. The impulses then aid in the release of endorphins that relieves pain naturally without any side-effects.

Non-Invasive Technique

Another one of the TENS Unit benefits is that it is a noninvasive technique to treat pain, starting with temporary to long-lasting relief. The electrical stimulation also does not intrude in any body part and cause harm of any sort.

Effective for a Plethora of Conditions

A TENS unit is proven to be effective for the treatment of different conditions. It has particularly been highly effective in allaying back and knee pain while providing relief to people suffering from different forms of arthritis. A TENS machine can be used by people who are suffering from urinary incontinence too as well as those who are suffering from mental health conditions, including depression and anxiety.

Effective and Efficient Complementary Therapy

A TENS unit can work as an effective complementary therapy to diverse kinds of intensive treatments. For example, a 2015 study that studied women suffering from pelvic pain related to endometriosis, credited TENS units as an effective complementary treatment to the intensive hormone treatment.

Pain Relief without Medication

People keep on popping pills and painkillers to address their painful body parts. But with a Tens unit, one can achieve pain relief naturally as it triggers the body to respond by sending endorphins and start healing quickly.

Portable & Easy to Use Machine

Tens machine is advanced tools that are perfect for domestic use (TENS Unit benefits). Place the pads on the muscle that requires stimulation, and the machine will work wonders. Unlike complicated units of the past, they are easy to use and set up. Users need to choose the right setting so that they can use it well.

Increased Circulation & Healing

This is the most admitted TENS Unit benefits by users. The Tens machine also overrides or blocks signals from nerves to the brain and thus aids in enhancing the local circulation of blood and increase the functionality.

Improved Sleep Patterns

Few users mention this as TENS Unit benefits. Reduced pain can aid your body to relax without having to worry about the injury or spasm at night. Hence one of the uses of a Tens unit is that your sleep quality will be better.

Benefits for Spasms & Knots

This is much discussed TENS Unit benefits. With the machine, you can relax your overworked muscles that have become knots. TENS units are one of the best treatment options that can help out with spasms and knots owing to its pain alleviating effects. Knots and spasms tighten the muscles in the place of injury to protect the area from further harm. TENS machines ease the pain and reduce the tightness. A recent study revealed that TENS therapy coupled with stretching therapy could be really effective in reducing the hardness of muscles resulting in a better range of motion.

Decreases Pain Signals

It is proven as TENS Unit benefits.. A TENS unit can help to reduce or block pain signals, ensuring pain relief immediately. The machine stimulates the nerves to decrease the pain signals, and the same stimulation blocks the signals from reaching the brain.

Increased Motion and Function

The TENS unit can be used with other treatment forms, and in pain can be used as a part of relaxation therapy, guided imagery, physiotherapy, and even for spinal manipulation for better motion and function of your body.

Natural Massager

Many companies are offering Tens units as massages and pain relievers with different intensity levels based on how you want to attend to your muscles internally. Even standard units are easy enough for users to essentially massage themselves anytime (TENS Unit benefits).

Retrains Nerves Effectively

While reducing pain signals, many studies reveal that a TENS machine can retrain nerves, especially for those who are suffering from some nerve damage. Additionally, as mentioned above, the use of the TENS machine will also stop the nerve from sending pain signals to the brain.

Reduced Inflammation

Inflammation causes huge discomfort and pain to the body. With proper stimulation, tens machine can aid in reducing inflammation happening deep within the muscle fibers. Tens machine can also help in relieving pain from pinched nerves, sciatica, and back pain (TENS Unit benefits).

Quicker Rehabilitation and Reduced Fear

Pain can easily lead to fear even for doing any task during the day. Without redressal of pain, the time taken for rehabilitation becomes even longer or leads the person to develop a phobia that restricts their movements and activity. One of the uses of Tens units is that users can reduce inflammation and redness pain, thus getting back to their regular level of activity. A person then can truly live their daily life without any unwarranted fear, using their complete level of strength without having to worry about muscle atrophy. With a Tens unit, people suffering from advanced knee and back pain can get back to normalcy way faster than the others.

Less Fatigue and Tiredness

Fatigue is sure to affect everyone having a hectic life, but one is so focused on energy to bear up the pain, that one is easily tired after a long day at work. The Tens unit helps in stimulating muscles and nerves and thus reduce fatigue levels drastically.

Affordable Pain Relief Solution

Many health gadgets found in the market are quite pricey, and not many can afford such gadgets to boost health. The Tens machine is significantly less priced and way more effective than others.

No Adverse Effect

Since it is not an invasive machine, the Tens unit can help scores of people who have to work day in and day out to withstand the pain of different types. It can relieve pain in a jiffy allowing the body to respond naturally.

What TENS is used for?

TENS may be able to help reduce pain and muscle spasms caused by a wide range of conditions including:

It’s also sometimes used as a method of pain relief during labour.

  • Transcutaneous – means through the skin.
  • Electrical – TENS machines deliver small electrical pulses to the body via electrodes placed on the skin. TENS machines are thought to affect the way pain signals are sent to the brain.
  • Nerve – pain signals reach the brain via nerves and the spinal cord.
  • Stimulation – if pain signals can be blocked by the tiny electrical shocks from the TENS machine then the brain will receive fewer signals from the source of the pain.

TENS machines are thought to work in two ways:

  • On a high pulse rate of 90-130 Hz (the normal method of use), the electrical impulses generated by the TENS machine interfere with and block pain messages sent to the brain. This is due to the gate control theory of pain. This proposes that there is a gate mechanism in the brain and spinal cord nerves (the central nervous system). When the gate is open, pain messages get through to the brain and we feel pain. When the gate is closed, these pain messages are blocked and we do not feel pain.
  • TENS machines are thought to stimulate certain non-pain-carrying nerves and close the gate. In effect, the brain is busy dealing with the messages it receives quickly from the TENS machine, rather than the slower (more painful) pain signals that the body is receiving from elsewhere. It explains why, if you injure yourself, rubbing that area can temporarily reduce the pain.
  • When the machine is set on a low pulse rate (2-5 Hz) it stimulates the body to make its own pain-easing chemicals called endorphins. These act a bit like morphine to block pain signals.


How to use a TENS Unit?

The information below is a general guide on how to use a TENS unit (machine). You should always follow the manufacturer’s specific instructions.

TENS machines are small and lightweight, so you can use them while you’re working or on the move. You can put it in your pocket, clip it to your belt or hold it in your hand.

You can use TENS throughout the day for as long as you like, although it shouldn’t be used while you’re driving, operating machinery, or in the bath or shower. 

Positioning the pads

Make sure the machine is switched off before you attach the pads to your skin. Position the pads either side of the painful area, at least 2.5cm (1 inch) apart.

Never place the pads over:

  • the front or sides of your neck
  • your temples
  • your mouth or eyes
  • your chest and upper back at the same time
  • irritated, infected or broken skin
  • varicose veins 
  • numb areas

Turning it on and adjusting the strength

Turn on the TENS machine when the pads are attached in the correct places. You’ll feel a slight tingling sensation pass through your skin.

The machine has a dial that allows you to control the strength of the electrical impulses.

Start on a low setting and gradually increase it until the sensation feels strong but comfortable. If the tingling sensation starts to feel painful or uncomfortable, reduce it slightly.

Switch the TENS machine off after you’ve finished using it and remove the electrodes from your skin.

Where to avoid placing TENS pads?

Side effects do not often occur when using a TENS device unless it is being misused. There are a number of places on the body where a TENS machine should not be placed. The following areas should be avoided when placing TENS pads on your body for use:

  • Eyes
  • Head
  • Spinal column
  • Over tumors
  • Open wounds (directly over; can be used around the wound)
  • Front of the neck
  • On the chest
  • Over a pacemaker or ICD device

Precautions

There are various types and brands of machine. Always follow the manufacturer’s instructions supplied with your machine.

Some general points:

  • TENS machines are designed so that you can move around with them working. You can tuck the machine into a pocket or clip it on to a belt.
  • Before placing the electrode pads on the skin make sure the machine is switched off.
  • Test the machine by holding the pads between the fingers and then carefully turn it on. You should feel a tingling sensation.
  • Make sure the skin where the pads are applied is clean and dry and there are no cuts, grazes or areas of skin irritation.
  • Place the pads either side of the pain. Use either self-adhesive pads or flexible rubber pads which should be completely covered, on the surface to be applied to the skin, with a thin layer of conductive gel. The pads should not be put within an inch (2-3 cm) of each other. Your physiotherapist or doctor will show you where to put the pads.
  • Fix the pads to the skin with tape if you intend moving around.
  • Set the pulse rate to the required setting (about 100 Hz is about right to start with).
  • Switch on the machine slowly and turn it up gradually until you feel a tingling sensation. The sensation needs to be quite strong but not uncomfortable. After a few minutes the sensation will start to drop away slightly. This is called accommodation. When this happens, turn the machine up slightly and then leave it for the rest of the time in use. Do not turn it up too high, as this can cause over-stimulation which may make pain worse. There should be no muscle contraction.
  • At the end of the session turn the machine off and disconnect the electrodes from the machine. If you intend using TENS again later there is no need to remove the electrode pads from the skin. Simply tuck the wires out of the way and carry on as normal.
  • Check that the pads or tape do not irritate the skin. If the skin is red you may need to use a different type of pad, contact gel or tape.
  • The machine should be used for at least 45 minutes but can be used for up to 12 hours before the electrodes need to be cleaned and re-sited.
  • When you have finished using the machine for the day, carefully remove the pads from the skin and clean the skin with ordinary soap and water. Do not pull directly on the wires to remove the pads. If there is any redness or irritation from the pads or tape then the next time you use the machine use a different area of skin.
  • If you use rubber pads, clean off the conducting gel with mild soap and water and rinse them well. Do not wash the self-adhesive type of pad.

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