Class IV Laser Therapy Benefits and How to Use - Dr. Axe

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Class IV Laser Therapy Benefits and How to Use


Class IV laser therapy - Dr. Axe

If you’re one of millions of adults who suffers from muscle aches, joint pain and limited mobility due to inflammation, you’re probably aware of just how many natural treatments are now available to help bring you relief.

While many treatments address only symptoms, but not always root causes of pain, certain types of light therapies — specifically class IV laser therapy — can provide more than short-term benefits, as it actually assists the body to help heal itself naturally without drugs or surgery.

For thousands of years, light has been considered a natural, healing source of energy. Today, we know that treatments with technologically-advanced laser devices can lead to beneficial, photochemical changes inside cells.

This process provides therapeutic outcomes including, but not limited to, the reduction and alleviation of pain or inflammation and an increase in blood circulation. The resulting improvement in range of motion and movement are essential to the recovery process.

A number of additional benefits include immunomodulation, promotion of wound healing and tissue regeneration. Laser therapy is known to be very safe, posing little risk for side effects, especially compared to long-term use of pharmaceuticals.


What Is Class IV Laser Therapy?

Low-level laser therapy or cold laser therapy is now referred to as photobiomodulation, to better define treatments from specific lasers that are used for pain relief and healing. Treatments are site specific on one or more areas of the body.

What does photobiomodulation mean, exactly? “PHOTO” means light, “BIO” means life and “MODULATION” means change.

According to the North American Association of Photobiomodulation Therapy (NAALT), Photobiomodulation Therapy is defined as “A form of light therapy that utilizes non-ionizing forms of light sources, including LASERS, LEDs, and broad-band light, in the visible and infrared spectrum.”

The Food and Drug Administration (FDA) has grouped all lasers, for both medical and non- medical uses, into four classifications. “Class IV”  (or class 4) lasers include those that emit power in excess of one Watt. Eye protection is needed when using these lasers to limit reflected light exposure. The majority of scientific, industrial, military and medical lasers fall into this category.

Treatments with this type are laser are performed by positioning its output, using a laser handpiece, either directly on the skin or approximately one-half inch above the surface and surrounding the area of injury and pain.

How Does Class IV Laser Therapy (Photobiomodulation) Work?

Laser therapies stimulate metabolic processes at the cellular level. There are many types of therapy available, depending on the power level, wavelengths and how they interact with the body.

Photobiomodulation is different than laser therapies that have applications in dermatology treatments (like acne) and ophthalmology (eye) procedures.

Photobiomodulation relies on four key parameters of laser technology:

  1. The type of light
  2. The role of wavelengths
  3. The operating modes
  4. The power or energy density

Class IV laser devices use laser diodes that are the “engine” of the products. These diodes determine the power level and the wavelength of the light that’s emitted. Recently, new technological developments have resulted in advanced lasers that are high-power, multi- wavelength devices that include red (635nm) and infrared (810nm, 980nm and 1064nm) wavelengths.

A key difference that makes this treatment better than other therapeutic modalities is photobiomodulation provides energy to cells that causes a series of chemical changes, resulting in the body essentially healing itself.

The Photon (light) energy is able to effectively penetrate the skin and underlying structures, accelerating the body’s recovery process. This photochemical mechanism of action triggers a cascade of cellular actions that include:

  • Stimulation of ATP
  • Stimulation of respiratory chain
  •  Increased DNA and RNA synthesis
  • Enhanced collagen synthesis
  • Increased levels of beta-endorphins and serotonin

FDA Classification as Medical Devices

Class 4 laser therapy is most often administered in a healthcare or medical professional office. Since they are high power devices, class IV lasers have consistently been shown to be clinically effective. They are classified as “Class II medical devices,” another reason they are different than other types of lasers.

What does this classification mean? In the U.S., the Food and Drug Administration (FDA) is the government agency that’s responsible for protecting the public health by regulating consumer products, including food, medications and medical devices.

Class II medical devices “pose a medium risk,” according to the FDA. This category represents 43 percent of all devices and includes a wide variety of devices — from motorized wheelchairs to the Apple Watch ECG app. The reason these lasers pose a risk is mostly due to their power and ability to affect the eyes if not handled properly.

The Center for Devices and Radiological Health (CDRH) is a regulatory bureau within the FDA that has the role of implementing and enforcing the laws and regulations which apply to radiation-producing electronic products. This category includes medical devices that include lasers and light devices. There are three different classifications of medical devices through the FDA and CDRH: Class I, II and III.


Using a device that hasn’t been listed, cleared or approved by the FDA as a medical device can be very dangerous because the device may be unsafe or ineffective. This is why it’s important to do your research, ensuring you’re being treated with a quality-controlled laser.

Potential Benefits

The expanding development of Class IV therapy lasers represents the next generation of light therapy. This type of laser is fairly new on the therapeutic laser scene and gaining interest from doctors who treat a wide variety of conditions. Many have used cold lasers or low-level lasers in the past, with limited or inconsistent clinical outcomes as confirmed in a number of published studies.

Class IV lasers represent a new opportunity for doctors with low-power lasers to add technology that will result in improved outcomes. Doctors that are new to photobiomodulation now have higher confidence levels and enhanced incentives to add this “drug free” treatment to their practice.

What does research tell us about potential Class IV laser therapy benefits? Some of the most popular applications for this type of laser treatment are:

1. Can Reduce Inflammation, Aches and Pains

Intended uses of Class IV laser devices include:

  • Promoting relaxation of muscles and providing relief from muscle spasms
  • Reducing minor joint aches, pain and stiffness
  • Temporarily decreasing arthritis symptoms
  • Helping to increase blood circulation

A recent review of published studies has found that photobiomodulation treatments appear to be “effective, safe treatments in a variety of conditions,” when devices were used for indications “including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects.”

Class IV laser treatments are unique because they don’t rely on heat to dull pain and boost blood flow. Their mechanism of action is photochemical, meaning that light energy causes chemical reactions inside cells that help to reduce inflammation and pain. This is a key, distinguishing factor that sets these treatments apart from other approaches.

Class 4 lasers are also now being recognized as optimal devices for reaching deep tissues that are tied to pain. Higher doses of light and higher output are needed to deliver appropriate doses of energy, due to the large portion of light that is absorbed, reflected or scattered at the skin’s surface. Less powerful lasers may not work if they cannot penetrate deep enough to provide any stimulating effect.

Other considerations in the overall depth of penetration and success of treatment include specific wavelengths and how they interact with the skin. Some light is absorbed more at the surface with darker skin or hair color than another wavelength. Additional features of a medical laser can include continuous wave or pulsing operations that also assist in achieving better results.

2. May Help with Recovery from Acute and Chronic Injuries

Using Class IV laser therapy for overcoming both acute and chronic injuries, such as tendonitis or damage to the knees, are among the most common applications. Not only do treatments address damaged tissues in specific areas of the body (knees, shoulders, back, etc.), but they also affect related issues. Overcompensation in some muscles, back pain or poor posture tied to overuse and inflammation may be improved.

Treatments have been shown to provide relief and boost recovery by reducing pain and inflammation as well as stimulating nerve regeneration, muscle relaxation and immune system response.

3. Used to Treat Skin Conditions Including Wounds and Scars

Emerging research, in both human and veterinary applications, suggests that photobiomodulation can lead to significant stimulation of healing in many types of wounds, burns and scars. Therapy lasers are used on a regular basis for managing wounds in the veterinary market (feline, canine and equine).

However, lasers are not currently cleared by the FDA specifically for wound therapy in humans. A physician may use a therapy laser for wound care but this would be considered off-label usage. It is anticipated that these applications will be become more prevalent as new studies are published and the FDA grants specific clearance.

Additional post-surgery applications with therapy lasers are emerging as a viable treatment to reduce infections and induce faster healing times, by up to 50 percent, for surgical incision sites.

4. May Help Treat Neuropathy

Therapy lasers are increasingly being used as an effective treatment for neuropathy and there are a number of clinical studies indicating positive outcomes. While this application is not yet cleared by the FDA, a physician may promote the use of a therapy laser for “treating the symptoms associated with neuropathy.”

Currently, podiatrists and chiropractors use therapy lasers primarily to treat neuropathy of the feet.

Since the first Class III lasers were cleared by the FDA in 2002 and the first Class IV lasers in 2003, the majority of treatments were performed in a medical office and most often by a chiropractor. With the newer models of high power or high intensity Class IV therapy lasers, treatments are now available from a growing number of medical professionals that include physical therapists, athletic trainers, podiatrists and medical doctors (MD and DO).

Some companies in the laser therapy business have been selling lasers on the internet for home use, often touting the same results as devices used in a medical office. These lasers are typically Class I, II, III or LED products and will have little or no therapy benefits due to their low power.

It is important to know that there may be a “Placebo” effect when using any medical laser or LED device. This means that a person may use it for the first time and perceive a benefit, but with repeated use there is no more benefit and no consistent clinical outcomes.

Many companies selling home-use lasers are also not registered with the FDA and have products that may be unsafe to use in addition to nominal or zero results. When in doubt about buying a product for home use, research the FDA website and also consult with a medical professional.

Both under-dosing and under-treating with lasers can result in less response and improvements. A powerful product like a Class IV laser is essential for providing the most benefits.

Although Class IV therapy lasers are most often administered in medical settings, they can be acquired for home use, too. Individuals that purchase Class IV lasers often choose this for financial reasons if they have a condition that may require ongoing treatments, or for usage reasons if they do not live near a medical office with a suitable device. Professional athletes may obtain a Class 4 laser to facilitate access to treatments during travel.

However, it’s very important that laser treatments be administered by someone, such as a family member or friend, following proper instructions and with the use of eye safety goggles. If being used at home, the environment should always be secure and free from potential distractions.

Which Type of Laser Should You Consider?

There are a number of Class IV therapy laser companies, but one manufacturer is emerging as a leader in the medical industry due to its ongoing research and development of technology that will provide the best clinical outcomes.

This company, ASPEN Laser, with corporate headquarters in Lindon, Utah, is FDA Registered since 2014 with multiple FDA 510k clearances. Their therapy laser products provide a unique combination of light wavelengths, operating modes, and power and energy density options for a broad range of treatment options. This allows clinicians to use the appropriate wavelength of light and parameters to treat a variety of conditions with consistent and positive outcomes.

Purchasing a laser with the broadest range of options allows medical professionals and individuals to determine the best laser model for their specific needs and applications, while also providing a range of price levels.

How Long Does It Take for Laser Therapy to Work?

According to Charles Vorwaller, President and CEO of ASPEN Laser, many patients usually see results quickly after being treated with these lasers. A typical treatment is 10 minutes and is painless with noticeable results of reduced pain and inflammation often in the first session. Many conditions may be resolved in 4 to 6 treatments over a period of time, while others may require additional sessions or periodic therapy.

ASPEN Laser devices can be used in a single-therapy treatment regimen, or as an adjunctive therapy in combination with other manual techniques. This includes treatment by physical therapy, chiropractic, massage therapy, acupuncture, etc.

How Much Does a Class IV Laser Cost?

Cost depends on the specific laser product you purchase or where you are being treated, and whether your insurance helps to cover treatment expense. Prices can also vary considerably depending on the device’s power level and features, number of treatments needed, and the severity of symptoms.

There are a number of Class IV therapy laser companies that are registered with the FDA and offer lasers with FDA clearances. Some companies providing lasers that are not FDA cleared often sell to the veterinary market. The prices for Class 4 laser devices have a wide range from $19,000 to $130,000.

Risks and Side Effects

As explained above, class IV lasers are classified as medical devices. To receive FDA approval for these devices, manufacturers must demonstrate sufficient, valid scientific evidence that there is a reasonable assurance that the devices are safe and effective.

When performed by a qualified practitioner or at home following directions carefully, this type of laser therapy is associated with very few side effects, often much less than pharmaceuticals. Because they are drug-free, non-invasive and non-toxic, they are considered safe and unlikely to cause side effects.

Using these lasers does require the use of eye safety goggles during treatments (an FDA requirement for Class IIIb and Class IV lasers). Following directions carefully is very important for avoiding skin and eye reactions, and for preventing any type of fire hazard.

Are there any class IV laser therapy contraindications to be aware of? Speak with your doctor if you have sensitive skin or eyes. Make sure to let your doctor know about any medication you’re taking and other treatment approaches you plan on combining with laser therapy.

Final Thoughts

  • What is Class IV laser therapy? It’s a class of low-level laser treatment that is used for pain relief and healing by photobiomodulation.
  • Class IV lasers are considered Class II medical devices. This form of light therapy is usually performed in a medical setting but may also be used at home.
  • Treatments are site specific to parts of the body, and benefits include lowering inflammation and pain while improving injuries, wounds and skin conditions.
  • Many people see results within one to five treatments, which are often 5-10 minutes
  •  Side effects are low, but eye protection must be worn to be safe.

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