The Pros And Cons Of Using TENS Units For Low Back Pain

If you are one of millions of Americans who suffer from chronic low back pain there is a good chance that you have tried almost every trick in the book to get rid of the pain.

Traditional remedies generally focus on medications such as ibuprofen and acetaminophen, or using heat or cooling packs. Unfortunately, though, most of these remedies are somewhat limited in their effectiveness and people often find that their low back pain continues to flare up.

It is no wonder then, that many people are left wondering about alternative treatments, such as TENS units for low back pain, and wonder if they might work to help relieve pain and get them mobile again.

What Is A TENS Machine?

A TENS unit is a transcutaneous, electrical nerve stimulator. It works by delivering small electrical impulses to your muscles through electrodes that attach to your skin. It sounds a bit scary but there is some sound science behind this new type of treatment.

The TENS unit basically sends electrical impulses through your body to stimulate your body’s own natural pain-relieving response. These electrical impulses release endorphins that stop pain signals in the brain.

How Does A TENS Machine Work?

TENS units can produce different frequencies which are either low frequencies, or high frequencies. The intensity of the impulse can range from a simple sensory response (where your body just feels pain) to a more intense motor response, where the strength of the impulse can actually cause your body to respond, physically, with an action.

Sensory (or low intensity) signals are where the electrical impulse is strong, but comfortable, and it doesn’t affect your motor system. High intensity impulses are not painful but they often produce a physical reaction from your motor system.

Interestingly, both frequencies produce different analgesic (pain reducing) responses by working on different opioid receptors in the brain.

Tolerance Build Up

Having a product that prevents pain without using pharmaceutical products sounds wonderful, and it is, to some extent. Unfortunately, over time, people often build up a tolerance to TENS signals. Studies have found that by day 4 of repeated use, the opioid receptors of the body build up a tolerance to the TENS impulses.

Over the past few years, however, more research has been done to see if, or how, this tolerance build up can be prevented. Researchers have found that blocking certain receptors in the body can delay this tolerance build up by about 5 days.

More studies are trying to see if alternating high and low frequencies (instead of using just one consistent frequency) could delay the onset of tolerance even more.

While the research is promising, it still isn’t the best news for those who are trying to treat low back pain themselves, in a home setting. It also shows that we need more research on this solution as it is a great option to help decrease the use of pharmaceutical solutions for low back pain.

How To Use Different Frequencies

New studies and clinical trials are currently underway to examine the effects of different frequencies on different conditions. TENS can be effective for both chronic and acute pain conditions, it just depends on how you use the stimulation. Both high frequency and low frequency TENS have been shown to reduce pain, especially when they are applied at a strong intensity.

Interestingly, studies have shown that high frequency TENS may be more effective for those individuals taking opioids for their condition. It is important to make sure that you use the strongest intensity possible, while still making it comfortable to the user, so that you can get the effects of hypoalgesia — a reduction in pain sensation.

Current research is indicating that using lower intensity frequencies is often ineffective when trying to treat pain. In fact, using TENS at inadequate intensities is one of the main reasons for the conflicting reports of its effectiveness. It is vitally important to make sure that you use your TENS unit at the maximum tolerated intensity to ensure a good response.

TENS Units For Low Back Pain: Conflicting Results

High-frequency TENS signals seem to be best for acute pain conditions, while low frequency showed positive effects at 32 weeks. A meta-analysis study showed positive effects of TENS for the relief of chronic musculo-skeletal pain, but other back pain studies have not always been able to replicate these results due to poor study designs and small sample sizes.

Clinical Research Around TENS

The lack of research may be a key reason that more studies on TENS mechanisms for individual pain conditions is so important. Potential users need clearer answers on the effectiveness of TENS for low back pain and musculoskeletal conditions.

One of the latest trials was published as recently as 2022. Unfortunately this study was simply a meta study that didn't include any new research - simply a review of of 381 randomly controlled trials. The authors of the study found that "there was moderate-certainty evidence that pain intensity is lower during or immediately after TENS compared with placebo and without serious adverse events".

The authors did note, however, that the levels of evidence were downgraded because all of the trials were small in size and had limited data with poor adverse event reporting. Again, more data, with more robust evidence would help people make a more informed decision about this therapy.

What types of conditions can you use TENS for?

TENS units can help reduce pain in some of the following conditions:

1. Arthritis & joint pain

2. Back and neck pain

3. Fibromyalgia

4. Musculo-skeletal pain

5. Neuropathic pain

Who Should NOT use a TENS unit?

You should definitely NOT use a TENS unit if you have any of the following:

1. A cardiac pacemaker or defibrillator

2. In-dwelling pumps or monitors

3. Spinal cord stimulator

4. Any implanted metallic or electronic device.

What Reddit Users Say About TENS for Back Pain

We gathered insights from real users who shared their experiences with TENS units. Here are the key takeaways:

1. Temporary Relief, but No Long-Term Fix

Many users reported that while TENS units helped ease pain while in use, the relief stopped once the device was turned off.

• "It feels amazing but only works while it’s on. It didn’t give me any relief at all once I turned it off." 

• "TENS units do what they're designed to do. Numb the pain while it's on and that's it. It doesn’t fix the root cause of the problem." 

  
  

2. Effectiveness Varies by Pain Type

Some users noted that TENS worked well for muscular pain but was less effective for nerve-related pain or structural issues like herniated discs.

• "My husband has upper neck, traps, and back pain and loves his TENS machine. His pain and issues are 100% muscular. It always helps him. I have a torn, herniated disc and pinched nerves and it does nothing for me. So it depends probably." 

  
  

3. Helpful for Managing Pain in Specific Situations

Users found TENS units particularly useful in certain situations, such as during long drives, before sleep, or when dealing with muscle spasms.

• "I like them for long drives. It helps move those muscles around a bit, so they don’t become tense as quickly." 

• "It took away my neck spasms and helped me sleep without pain." 

  
  

4. Potential Downsides: Skin Irritation and Overuse Issues

One user experienced a skin reaction due to prolonged use, possibly from an allergic response to the electrode pads.

• "I bought a TENS unit and it allowed me to function more normally. The problem was I overused it, and it caused a skin reaction that needed GP intervention." 

  
  

5. Device Quality Matters

Several users noted that not all TENS units are created equal. Higher-quality devices, especially those with larger electrode pads or wearable belt designs, seemed to be more effective.

• "There are different quality devices as you can imagine. The best one I had was one that connected to a large pad that you wore like a belt." 

The Verdict: Should You Try a TENS Unit?

Based on these real-world insights, TENS units seem to provide temporary pain relief, especially for muscular pain. However, they are not a cure for chronic pain and may not be effective for nerve or structural issues.

If you’re considering trying a TENS unit, here are some tips:

• Use it intermittently rather than continuously to avoid skin irritation.

• Pair it with other treatments like physical therapy, stretching, or medication for a more comprehensive approach to pain management.

• Invest in a high-quality device with adjustable settings and larger pads for better coverage.

• Consult with a healthcare provider if you have underlying conditions or concerns.

  
  

Conclusions

TENS units are a promising, low-cost option for managing low back pain, especially for those looking for an at-home or travel-friendly alternative to medication. While they don’t work for everyone, many users find them helpful for temporary relief in specific situations. However, it’s important to note that research on their effectiveness is mixed, and results can vary from person to person.

To get the most benefit from a TENS unit, understanding how to adjust intensity and frequency is key—both to maximize pain relief and to prevent rapid tolerance buildup. Most importantly, always consult with your healthcare provider before starting a new treatment, especially if you have an implanted medical device, as TENS signals may interfere with it.

Have you used a TENS unit for pain relief? Share your experience in the comments or on our social pages—we’d love to hear from you!