What is Cold Laser Therapy?

The Evolution of Light Therapy

Cold laser therapy is relatively new compared to alternative therapies like acupuncture (used since 800 B.C.), chiropractic (since 1895), and physical therapy. Just as the abacus evolved into the computer, many alternative medicine practices are now evolving to include laser therapy.

The first cold laser received FDA clearance in 2001. Since then, innovations in low-level laser technology have made it possible for both practitioners and consumers to own high-quality equipment. Cold lasers are also called Low-Level Lasers (LLL), soft lasers, or the therapy is referred to as photobiomodulation (PBM) or low-level laser therapy (LLLT).

Today, lasers are used extensively in traditional medicine for cosmetic surgery, eye surgery, and heart surgery. The ability to deliver precise energy to specific areas of the body has been a huge medical advancement. Cold lasers are an important addition to these established treatments, and recent development of affordable professional systems means cold laser therapy is rapidly growing as a treatment option.

Two Treatment Approaches

Cold lasers can be used in two distinct ways:

1. Direct Treatment

Treating damaged tissue directly to promote ATP production, reduce inflammation and pain, and support recovery. This is the most common approach and typically delivers the highest efficacy for musculoskeletal conditions.

Example: Treating a knee injury by applying the laser directly over the damaged ligaments and surrounding tissue.

2. Indirect Treatment

Treating areas of the body that control or support the main therapy plan—similar to acupuncture but without needles. This targets trigger points, acupuncture meridians, lymph nodes, or the nervous system.

Example: Treating acupuncture points on the ear or hand to address conditions elsewhere in the body, or stimulating lymph nodes to improve drainage.

How Cold Laser Therapy Works

Cold lasers produce impulses of light at specific wavelengths (typically 600–980nm) that minimize reflection and scattering while maximizing absorption of photon energy at the desired tissue depth.

The Science: Photobiomodulation

The goal of laser therapy is to deliver light energy units (photons) from red and infrared laser radiation to damaged cells. The scientific consensus is that photons absorbed by cells stimulate the mitochondria to accelerate production of ATP (adenosine triphosphate)—the fundamental energy currency of all cells.

This biochemical increase in cellular energy transforms cells from a state of illness or damage to a stable, healthy state. The process is called photobiomodulation because light (photo) is modulating biological processes at the cellular level.

Wavelength & Penetration Depth

Different conditions require different penetration depths. Some conditions like deep joint pain require penetration of 4–5 inches, achievable only with powerful laser emitters at optimal wavelengths (typically 800–860nm).

For shallow tissue treatment (lymphatic system, surface scars), shorter wavelengths (600–700nm) are more appropriate. Red light at 630–680nm adds energy to the shallowest tissue levels.

General consensus: Wavelengths below 660nm are easily absorbed by surface tissue and aren't optimized for deep tissue treatment. Products like the Avant and TerraQuant operate in both lower and upper wavelength ranges, providing flexibility for different treatment depths.

Biological Effects of Laser Therapy

Increased Cell Growth

Laser photons support cellular reproduction and growth, accelerating the body's natural repair mechanisms.

Increased Metabolic Activity

Photons initiate higher enzyme outputs, greater oxygen delivery, and increased ATP production—the basic energy source for all cellular functions.

Faster Wound Recovery

Stimulated ATP production leads to fibroblast development and accelerated collagen synthesis in damaged tissue.

Anti-Inflammatory Action

Laser photons reduce swelling caused by bruising or joint inflammation, resulting in enhanced mobility.

Increased Vascular Activity

Photons induce temporary vasodilation, increasing blood flow to affected areas and improving nutrient delivery.

Reduced Scar Tissue

Laser treatment reduces fibrous tissue formation following cuts, scratches, burns, or surgery.

Stimulated Nerve Function

Photon exposure may speed nerve cell reconnection, helping to reduce numbness and restore sensation.

Pain Reduction

Almost all systems have modes specifically designed for pain control through multiple mechanisms including endorphin release.

Conditions Treated with Cold Laser

Cold laser therapy offers a non-intrusive alternative to surgery and a non-addicting treatment that eliminates complications of long-term drug programs. Cold lasers are FDA cleared for pain control, inflammation reduction, and increasing blood flow. These core clearances allow treatment of a wide variety of conditions:

Pain & Inflammation

Acute and chronic pain
Arthritis
Back pain
Fibromyalgia
Bursitis

Soft Tissue Injuries

Ligament sprains
Muscle strains
Tendonitis
Tennis elbow
Soft tissue injuries

Nerve & Joint

Carpal tunnel syndrome
Neuropathy
Joint pain
Post-surgical recovery
Wound care

Benefits of Cold Laser Therapy

For Patients

Non-invasive—no surgery, no needles
No side effects or pain during treatment
Non-toxic with no drug interactions
Non-addicting alternative to pain medications
Reduces need for surgery in many cases
Cost-effective compared to ongoing drug treatments

For Practitioners

Easy to apply with minimal training
Extremely safe with proper protocols
Highly effective (90%+ efficacy for appropriate conditions)
Superior alternative to analgesics and NSAIDs
Works synergistically with chiropractic, acupuncture, and PT
Excellent ROI with high patient satisfaction

Understanding Laser Classes

The U.S. government classifies lasers based on their potential for eye damage. Many manufacturers push power levels as a marketing tool—and while power is important, more isn't always better. Understanding laser classes helps you choose appropriately for your needs.

Class 1 & 1M

Over-the-Counter

Class 1 lasers are the safest—so safe they can be purchased for home use without restrictions. Simple continuous-wave Class 1 lasers have very low power, but modulated, pulsed, and super-pulsed lasers provide higher power levels while still qualifying as Class 1.

These pulsing lasers are off enough of the time to have minimal eye damage risk. Because of lower cost, Class 1 lasers are widely used in practitioners' offices with proven track records.

Class 1M lasers are the best over-the-counter option. Limited to 500mW maximum, they can't cause eye damage unless the beam is focused. Treatment times are typically longer than higher-power products.

Example: TerraQuant series. Be cautious of anything resembling a laser pointer—it's quite possibly an overpriced pointer with no therapeutic value.

Class 2

Over-the-Counter

Since the development of Class 1M lasers, Class 1 (without the M) and Class 2 lasers are now the weakest on the market—often about 1/500th the power of Class 1M or Class 3B systems.

This class is slowly being phased out as better options become available.

Class 3B

Professional / Supervised Home Use

Class 3B lasers are classified when max power is less than 500mW per diode. Many devices have multiple diodes, so total power can be higher. These typically require a target light since infrared wavelengths are invisible but can still damage eyes.

Safety features may include warning tones, key locks, or interlocks. Some manufacturers have tested systems that deliver higher power per diode (up to 700mW) while maintaining Class 3B safety standards through beam design.

Example: Avant LZ30 series—delivers up to 2.7 watts total power through multiple diodes while maintaining Class 3B safety classification.

Class 4

Professional Use Only

Class 4 lasers have the highest potential for eye damage and can damage tissue if used improperly. Tissue damage is rare, and manufacturers develop protocols balancing power and safety—but misuse can cause harm.

Any single laser beam over 500mW classifies as Class 4, but many popular models use multiple beams. Some Class 3B lasers actually have higher combined power than entry-level Class 4 systems. Many lasers diverge beams at 28–30 degrees for wider coverage and safer delivery.

The increased power shortens treatment times—critical for busy pain clinics but less important for average users. All Class 4 lasers require safety interlocks to prevent accidental exposure.

Example: Some systems use 4 divergent beams to produce 5+ watts without tissue damage risk (eye protection still required).

Important: Laser class is proportional to eye damage potential—but NOT proportional to treatment efficacy. There are products with too little power to be effective and products with more power than most users need. The right choice depends on your specific application.

Quick Comparison

Class	Power Range	Availability	Treatment Time	Best For
Class 1M	Up to 500mW (pulsed)	Over-the-counter	Longer	Home use, general wellness
Class 3B	500mW–2.7W	Professional / Home	Moderate	Clinical use, dedicated home users
Class 4	3W–60W+	Professional only	Shortest	High-volume clinics, deep tissue