|To Your Health
April, 2010 (Vol. 04, Issue 04)
Show Me the Light: The Healing Power of Laser Therapy
By Dr. Phil Harrington
They are in supermarket scanners and compact disc players, and can shoot down
satellites. They can measure the distance from the Earth to the moon within a millimeter and repair your vision
with just one treatment.
They can cut steel, produce three-dimensional images and transmit telephone messages around the world. What
are they? Lasers. Theorized by Albert Einstein in 1917 and invented in 1960, lasers have proven to be
a versatile high-tech solution to many of life's problems. Today, more and more people are learning that
therapeutic doses of laser light can also relieve pain and expedite healing for a wide range of health complaints.
An increasing number of doctors nationwide are offering laser therapy to their patients. With its increasing
popularity and use, that means more and more people are probably wondering about lasers in general and some
important specifics, including how they work, how safe they are and what it feels like to get treated. To answer
these questions and more, we interviewed Dr. Phil Harrington, a chiropractor who also has a degree in physics.
What is laser therapy?
Laser therapy is the application of low levels of laser light to areas of the body that have been injured or
damaged. Contrasted with high-powered lasers used in health care that cut tissue, such as surgical or hair-removal
lasers, therapy lasers produce beneficial photochemical and photobiological interactions that can help relieve pain
and repair injured/damaged tissue.
What is the history of laser therapy?
use of light as a healing modality has been recorded as early as 4,000 years ago in ancient Egypt. Albert
Einstein wrote a theory about lasers in 1917, and the laser was invented in 1960. Laser light is special
because it is monochromatic (one color), coherent (all waves are in phase with each other), and can be
collimated (held to a small spot size at a great distance). Dr. Endre Mester was the first to observe the
positive effects of laser when hair grew more quickly on shaved mice that were exposed to low levels of laser
How long have lasers been used by health care providers?
Therapy lasers have been used in Europe since Dr. Mester's discovery in 1967. The U.S. Food and Drug
Administration (FDA) gave market clearance to the first therapy laser in 2002. Since then, progressive
chiropractors, osteopaths, medical doctors and other have been offering laser therapy to their patients in
How do lasers work?
The photons of laser light penetrate through your skin and are absorbed by special components in your body's
cells called chromophores. Just as photosynthesis creates energy for plants, the absorption of the photons
by your cells causes increased production of cellular energy. In areas of injury or damage, this means there is
more energy available to improve the rate and quality of healing. This is called biostimulation.
Because of its biostimulatory nature, laser therapy has the potential to help any scenario whereby the body's
cells are not working to their optimum potential. Studies on tissue cultures reveal a wide range of beneficial
physiological effects, including increased levels of endorphins, prostaglandins and other beneficial components;
reduced levels of harmful compounds including C-reactive protein and interleukin-1; pain modulation through a
variety of mechanisms; and increased rate and quality of tissue healing.
OK, but what does that all mean in English?
For patients, that means relief from acute and chronic pain, reduced inflammation and muscle spasms, improved
range of motion and restored function. Patients suffering from headaches, neck pain, carpal tunnel, low back pain,
sports injuries, post-surgical pain and more have been helped with laser therapy.
How long does it take to work?
Some patients notice improvement after the very first treatment session; with others it may take a few
treatments. The effect of laser therapy is cumulative, meaning that each successive treatment builds on previous
ones. The main benefit to patients, as reported by laser therapy practitioners across the country, is that
chiropractic care plans that include laser therapy produce faster and better quality clinical outcomes.
What does it feel like to get a treatment?
With very low-powered therapy lasers, you feel nothing at all. Higher-powered (Class IV) therapy lasers produce
a mild, soothing, warm feeling. You may notice a tingling sensation in the treatment area as blood vessels dilate,
or that muscle spasms are reducing in strength and duration. Laser therapy is a painless treatment.
How do you know it not causing cancer or other tissue damage?
There are two ways that laser light can damage tissue; if it is very concentrated (high power density) or if the
photons are very high energy. Therapy lasers use power densities that are far below the levels that cause tissue
damage. Ultraviolet light has very high-energy photons capable of ionizing molecules, but therapy lasers use
visible and near-infrared light, which only cause molecular vibrations. You could argue that therapy laser light is
safer than sunlight.
Are there any side effects?
Some patients may experience soreness in the area of treatment, as toxins are released and blood flow is
restored. World experts on laser therapy have commented that therapeutic lasers have no undesirable side effects in
the hands of a reasonably qualified therapist. Laser therapy is safe, painless and inexpensive compared to
How do I prepare for a laser therapy treatment?
Since laser light does not pass through clothing, laser therapy must be delivered directly to the skin. Wear
clothing that can easily reveal the treatment area or you may need to change into a gown at your chiropractor's
Laser Therapy for Neck Pain: Good News
A recent review of studies,
results of which were published in the medical journal Lancet, concludes that low-level laser therapy is
immediately effective (as little as one treatment visit) for acute neck pain and effective up to 22 weeks following
multiple treatments for chronic neck pain. The study reviewed 16 previous studies and found laser therapy to be
effective overall, with results comparing "favorably with other widely used therapies, and especially with
pharmacological [drug] interventions, for which evidence is sparse and side-effects are common."
That's good news considering that neck pain is one of the most common and disabling conditions, accounting for
substantial lost workdays, diminished productivity, and use of over-the-counter medications. Talk to your doctor
for more information.
Phil Harrington, DC, is a certified medical laser safety officer and serves on the subcommittee
reviewing the ANSI Standards for Safe Use of Lasers in Health Care Facilities. He also holds a bachelor's degree in
physics and is the senior vice-president of K-Laser USA.