Low-Level Laser Therapy or Low-Level Light Therapy (LLLT)

Low-level laser therapy, sometimes called low-level light therapy or LLLT, is one of the newer procedures being used in the treatment of androgenetic  alopecia, or male and female pattern baldness. It is generally applied through the use of the laser hood or laser cap, or with hand-held devices such as the laser comb.

LLLT works by directing low-level laser light energy to the scalp tissue, in order to boost the blood supply, and stimulate hair growth cells beneath the scalp – a process known as Photo Biostimulation.


The link between low-level laser therapy and hair loss was discovered quite accidentally. In 1967, Hungarian physician Endre Mester began researching whether lasers might cause cancer. In his research, Mester shaved the hair off the backs of several mice, divided them into two groups and exposed one group to constant cold laser light. Not only did none of the mice contract cancer, but those that had been exposed to the laser light grew their hair back much more quickly than the untreated group. With this, Mester discovered “laser-biostimulation”. Mester’s discovery laid the groundwork for researchers to adapt laser-biostimulation as a treatment for human androgenetic alopecia.


Low-level laser therapy is a procedure that can be performed at home or, if preferred, in a medical setting with a physician. LLLT is completely non-surgical and painless, but as with all hair loss treatments, LLLT requires a long-term and patient commitment from the user. Any results will show only for as long as the treatment is continued. Proponents of LLLT are clear that it should be regarded as an ongoing treatment, not a cure, and may work best if used in conjunction with another hair loss treatment, such as a DHT blocker or after a hair transplant, to encourage the growth of stronger, thicker hair.

Users should beware of manufacturers that promise “instant results” or claim FDA clearance: in general, any benefits from LLLT will be noticed after 4-6 months of continued treatment. And, only one LLLT product – the HairMax LaserComb – has been given FDA clearance.

At present, there are three main techniques used in LLLT, each with their own advantages and disadvantages.

The Laser Hood

With this method, low-level laser light is directed at the scalp using a laser hood, similar in style to a salon’s hair dryer. The laser hood’s low-level laser light is directed at the scalp in order to increase blood flow, and encourage the growth of stronger, thicker hair. Treatments typically last from 15 to 30 minutes, occurring three times per week.

One of the obvious benefits of the laser hood is that it is a pain-free, non-evasive procedure. And as it is hands-free, the user can sit, relax, read a book or watch TV during the procedure.

The main slight against the use of the laser hood is its possible ineffectiveness for individuals with “too much” hair.  As the laser light needs to be directed onto the scalp, nearest the hair follicles, hair itself may block the light from reaching its intended target. The effectiveness of LLLT may be greatly diminished because of these obstructions between the laser light and the scalp.

The Laser Cap

Another option in LLLT is the use of a Laser Cap. As the name suggests, the Laser Cap fits against the skull much like a baseball cap, and can be easily concealed beneath a regular hat. Since it’s a hands-free process, users can do other things during treatment – even go outdoors. A portable, rechargeable battery pack ensures that the laser light is being constantly emitted, even while the user is away from home.

The Laser Cap is typically worn for 30 minutes, 3 times a week, unless the user’s physician specifies otherwise. Because the Laser Cap sits close to the scalp, laser light isn’t as obstructed by the hair as it may be with the Laser Hood. Perhaps the advantages of the Laser Cap are the fact that it can be easily concealed, it requires no handling, and treatment can be easily maintained wherever the user may be. While some companies suggest that results can be seen in as little as 90 days, most users see noticeable effects after six (6) months of consistent use.

However, The Laser Cap has one disadvantage to other methods: the cost. The Laser Cap is quite expensive, with single unit cost in the neighborhood of $3000.

The Laser Comb

The final option in LLLT is the Laser Comb. The laser comb is slowly passed through the hair for 10 to 15 minutes, 3 times per week, in order to deliver laser energy to the scalp. Unlike other methods, where hair may block the laser light, the laser comb’s teeth part the hair, allowing the laser energy to be directed right against the scalp. This greatly increases the chances of stimulating the hair follicles and giving the user the fullest advantages of LLLT.

The biggest advantage to the laser comb is its portability and, depending upon the design, the comb’s ability to direct laser light more closely to the scalp and hair follicles than other methods of LLLT. The only real disadvantage to laser combs in general is that they are not a hands-free product. Users have to commit to spending 10-15 minutes per day very slowly and deliberately combing through their hair.

Beyond the Only the HairMax LaserComb has FDA clearance that allows the manufacturers to market their product as a treatment for the regrowth of hair in males and females with certain classes of androgenetic alopecia. Some laser comb manufacturers suggest that all laser combs have been FDA-approved or that LLLT in general has been “FDA approved”, but this is not the case. If you decide to purchase a laser comb other than the HairMax LaserComb, be wary of manufacturer claims.


Most physicians and hair loss specialists recommend using LLLT in combination with another hair loss treatment – for example, prescription Propecia, topical Rogaine or post-transplant to encourage continued hair growth. Ideal candidates are those who are in the early stages of androgenetic alopecia.

The cost of low-light laser therapy depends upon the method you use to treat your hair loss.  If you invest in a laser hood for home use, you can expect to spend anywhere from $700 to $1500 and beyond, depending on the model.  The Laser Cap is most expensive, with a cost of around $3000. The HairMax LaserComb sells for approximately $550, while other laser combs retail between $130 and $600.

Side Effects

There are no documented side effects to low-level laser therapy. As the lasers are low intensity and cold, there is no risk of overheating or burning. Because of this, the treatment is safe, even if it extends past the manufacturer’s recommended time suggestions.

Links and Testimonials

Dateline NBC devoted an entire episode to “The Follicle 5” — five men with varying degrees of hair loss, who each agreed to test some of the most common hair loss products, medications and procedures (including the low-level light or laser therapy discussed on this page). View all five parts of this extensive, year-long experiment on YouTube.

Here is an overview on how low-level laser therapy works, from ABC Chicago, and another from CBS 2. Also, there is more information and testimonials from those who have tried LLLT on NBC Today.

More specifically, here’s information on the Laser Hood from CBS 5 News, and a testimonial from NBC Miami by someone who has used the Laser Hood.

Here’s a video review of the Laser Cap, followed by the same user commenting on his results.

Finally, How To Use The HairMax LaserComb lets you see exactly how the only FDA-cleared laser comb works.