What Laser Therapy (LLLT) Is
A laser device is held against the skin for several minutes during treatment, allowing the light to penetrate through the skin into the treatment area. Treatment may be repeated over several sessions for the best effects.
Although often seen as an alternative therapy, there’s an increasing amount of evidence that LLLT can help with musculoskeletal conditions and may also help to treat skin and soft tissue problems.
How Laser Therapy (LLLT) Works
LLLT is a noninvasive way to stimulate the body’s energy production, reduce inflammation and support tissue repair.
We don’t understand all the specifics around how this therapy works, but we do know that it targets the cells’ mitochondria (the energy-producing part of the cell).
LLLT increases mitochondrial production of a molecule called ATP (the main currency of energy within a cell) by stimulating the enzyme cytochrome C oxidase and modulating the release of the chemical nitric oxide (Lyu et al., 2022). These changes within the mitochondria help the body to move away from inflammation and encourage cell repair (Steele, 2025).
Outside of the mitochondria, LLLT also reduces the release of chemicals that support inflammation and stimulates production of anti-inflammatory chemical messengers. This helps to reduce pain, swelling and tissue damage while supporting the body’s ability to regenerate (Steele, 2025).
Many factors can impact how effective treatment is. The type of wavelength, power, energy level and pulsing technique can all affect the results. However it’s not just the laser that impacts treatment – your underlying health does too.
Mitochondrial dysfunction caused by lack of sleep and reduced vitamin levels that are important for mitochondrial health (such as CoQ10) may affect how well the body responds to LLLT, although this area of research is still ongoing and more human research is needed (Giménez et al., 2022; Salehpour et al., 2019).
Who Laser Therapy (LLLT) Helps
LLLT is useful treatment for a variety of inflammatory diseases, especially those affecting the skin and joints as they’re most accessible for treatment.
Most inflammatory diseases are typically treated with painkillers, medication to suppress the immune system or surgery, many of which have unwanted side effects. LLLT is a good add-on treatment that typically comes with fewer side effects but can help control inflammation and improve disease symptoms.
LLLT is useful for individuals looking to reduce inflammation and stimulate tissue growth/repair. It may be helpful for people hoping to avoid or delay the need for surgery and who want an alternative to standard medication-based treatments.
Common Uses
Low-level laser therapy or photobiomodulation devices are approved in the US for a variety of issues, including:
Temporary muscle and joint pain relief
Treating macular degeneration
Improving male and female-pattern hair loss (androgenetic alopecia)
These uses are fairly well supported and the FDA has cleared various devices for these purposes.
LLLT is also often used for supporting poorly-healing wounds, dermatological (skin) conditions, dental issues and for certain neurological conditions. The amount of evidence supporting these different applications varies.
What the Evidence Supports
There is the largest amount of evidence supporting LLLT as a treatment for musculoskeletal (MSK) conditions.
A meta-analysis of 22 randomized controlled trials (RCTs) found that LLLT significantly reduces pain and disability in knee osteoarthritis at the recommended wavelength and intensity (Stausholm et al., 2019).
Another review found that LLLT can help with a variety of sports injuries and MSK conditions, including chronic back pain, knee arthritis and pain after joint replacement (Gadah et al., 2025).
LLLT can also help with soft tissue injuries. A meta-analysis of 18 trials found that laser therapy could improve pain and disability in people with tendon issues and plantar fasciitis, with effective short and medium-term results (Naterstad et al., 2022).
In a review of 18 RCTs, LLLT was found to be superior to both placebo and standard care when used to support wound healing, pain management and reduce inflammation after oral surgery (Chaple Gil et al., 2025).
Other studies investigating LLLT for wound healing have found it to be an effective treatment. When analyzing 18 RCTs, LLLT was found to significantly reduce wound size in ulcers, burns and skin grafts and to improve wound pain for a variety of different wound types (Taha et al., 2024).
Additionally, a systematic review of 36 articles on LLLT for hair loss found that therapy improved both male and female-pattern hair loss symptoms without side effects (Gentile & Garcovich, 2021).
Where the Evidence Is Limited
Although LLLT seems to be effective for alleviating symptoms in multiple different conditions, it is not a cure. Most studies also focus on the short or medium-term effects of treatment, with limited data on the long-term impacts.
Most studies have investigated LLLT as a treatment for superficial health issues, with weaker evidence on its effectiveness for treating deep-tissue problems or neurological conditions (Chan et al., 2024; Lawrence et al., 2024).
There is also limited evidence around the optimal dose of LLLT. Different studies use variable wavelengths, power density, energy per point, number of points, exposure time and frequency. Although we do know that too high and too low a dose can impact effectiveness, more information around optimum dosing and protocol standardization is needed.
Safety and Regulation
Several LLLT devices are cleared by the FDA, including multiple devices for home use. However, results from home devices vary due to differences in quality and light types.
Each device is cleared for different purposes, including general pain management and more specific health conditions. The FDA hasn’t approved LLLT in general or for specific indications, but regulates LLLT by clearing individual devices for general use and set indications.
When used correctly, LLLT is generally considered safe. It’s mostly a well-tolerated treatment, with few serious side effects reported. Individuals can experience redness or dryness at the treatment site, with an occasional temporary increase in pain if the treatment dose is too high.
Serious side effects are unlikely. The main severe side effect is that LLLT can cause eye damage if pointed directly into the eyes without appropriate eye protection.
The Experience
You can receive LLLT from a provider at an in-person clinic (such as a physical therapy clinic, integrative-medicine clinic or dermatologist) or use a home device.
You’ll attend your appointment and lie/sit down while your provider moves a hand-held laser device over the treatment area, or applies a treatment cap/helmet to your head. The laser will then be used for around 5–20 minutes. During this time, you may feel a light pressure from the device or a mild warmth, but you may not feel anything.
You should not feel any pain, burning, tingling or other unpleasant sensations.
After treatment, you can immediately return to your normal activities and should start to notice improvements in your symptoms (although it may require multiple sessions before your symptoms start to improve).
If giving yourself treatment at home, the process is very similar but you are in control of the device. Make sure to avoid shining the laser into your eyes and follow the instructions enclosed with your laser device, including wearing eye protection if required.
The Future of Laser Therapy (LLLT)
It’s likely that laser therapy will continue to become more accessible, with more effective home devices coming onto the market in the future.
Protocols may become more personalized as we gather more data on the most effective LLLT strength and patterns for specific health problems.
LLLT may be used for additional indications in the future, but larger and higher-quality studies will be needed to confirm treatment effectiveness. Research into neurological applications (such as for traumatic brain injuries or dementia) seems promising so far, but more research is needed to determine the specifics around treatment (Chan et al., 2024; Saltmarche et al., 2025).
Takeaway
Low-level laser therapy (LLLT), also known as photobiomodulation or cold laser therapy, uses a low-power laser to relieve symptoms associated with a variety of health conditions. It works by supporting cellular energy production, reducing inflammation and supporting tissue repair.
LLLT is particularly effective for inflammatory diseases that affect the joints and muscles, but can be used to treat hair loss, poor wound healing and other problems. It can be a useful add-on to traditional treatments and usually comes with few side effects. However, lack of protocol standardization means results vary.
