Biofreeze is the well-marketed, strong-smelling green goo that's available in a spray, a gel, a roll-on stick, a variety of pumpers, a single-use wipe... well, pretty much every way a goo can be packaged.
Its own website boasts it as the #1 used and recommended topical pain reliever by chiropractors, massage therapists, physical therapists, and podiatrists.
The company that launched BIOFREEZE was Performance Health, Inc. They're not only the folks behind this green goo, but also THERA°PEARL, a very attractive looking heat/cold pack; and THERABAND, a whole line of neat stretchy exercise/strengthening helpers.
So, they helping out with muscular discomfort. That, and they really like capital letters.
Performance Health, Inc. was acquired by the Hygenic Corporation in 2006. Located in Ohio, they, "manufacture an exceptionally wide variety of natural and synthetic rubber tubing and sheeting products for medical, laboratory and industrial applications."
Exceptionally wide, huh? What does that mean?
Well, their daunting product and applications page answers that that question: from bakeries to dentist offices, laboratories, fitness centers, military bases, to this dog in a pool - they've got rubbery products for any setting.
According to their website: "Biofreeze was first introduced to the world by a medical professional who was searching for a way to help his grandmother manage her arthritis pain. The formula he created consisted of the active ingredient menthol with a synergistic blend of inactive ingredients. The resulting formula offered quick, effective pain relief without the use of prescription drugs."
Neat back story. So, how exactly does it work?
BIOFREEZE ACTIVE INGREDIENT
This an organic compound is made synthetically or obtained from mint oils. In the case of this product, the menthol makes up 4-10% of the product, depending on which specific product application you use.
Menthol (along with wintergreen oil, eucalyptus oil, camphor, and turpentine oil) is known as a counterirritant. Counterirritants create a feeling of cold or heat that can overpower the painful joint or muscle.
Menthol enhances cooling sensations via stimulating the cold-sensitive transient receptor potential channel melastatin 8 (TRPM8). This receptor is responsible for the well-known cooling sensation it provokes when inhaled, eaten, or applied to the skin.
Menthol also has weak analgesic (pain-killing) effects due to select activation of the κ-opioid receptor. This receptor is a protein that mediates a variety of effects including changing our perception of pain, consciousness, motor control, and mood.
Biofreeze's website provides some diagrams explaining the effects of menthol:
BIOFREEZE SIDE EFFECTS
There are no known major side effects for using Biofreeze as advised (on the skin, external use only), although one should seek medical attention if a severe allergic reaction occurs.
It's also not a good idea to use on broken or damaged skin, and be sure keep it clear of the eyes - ouch.
I found an established body of research that may suggest the use of menthol for mild pain relief. Given the very low risk and very limited side effects, it would seem worth a try for individuals seeking a complementary and/or off-the-shelf product for pain relief.
Where can you get it? Like stated before, many chiropractors, physical therapists, and massage therapists carry this brand. Also, some big box stores carry Biofreeze. You can also find it on Amazon in a roll-on, 4 ounce tube, or 32 ounce pump bottle.