Photobiomodulation (PBM)
What Is It?
Plain-Language Explanation
Photobiomodulation (PBM), also known as low-level laser therapy (LLLT) or red-light therapy, uses red or near-infrared light from a medical LED panel or low-power laser to stimulate cellular repair. The light is absorbed by tiny structures inside cells that generate energy, helping those cells function better and reducing inflammation.
The procedure is painless and produces no noticeable heat. The device is held near the treatment area for 5–20 minutes. There is no harmful radiation involved.
Technical Explanation
PBM acts via photon absorption by the primary chromophore cytochrome c oxidase (CCO / mitochondrial complex IV) at wavelengths of 630–700 nm (red) and 800–1070 nm (near-infrared). Photon absorption enhances electron transport chain activity, increases ATP production, and modulates reactive oxygen species (ROS) at subtoxic levels.
Secondary effects include NF-κB transcription factor activation, nitric oxide (NO) synthesis via photodissociation, and downregulation of pro-inflammatory cytokines (IL-6, TNF-α). In neural tissue, evidence supports increased BDNF expression and protection against post-ischaemic neuronal apoptosis.
How It Is Used at Our Practice
In our practice, PBM is applied using a medical-grade LED panel or Class 3B laser probe with individually calculated fluence (energy dose) based on the clinical indication. Application may be transcranial (targeting cortex) or directed at peripheral nerves and musculoskeletal tissue.
PBM is frequently combined with other modalities such as tES or dry needling as part of an integrated recovery protocol, particularly in neuropathic pain, post-stroke rehabilitation, or cognitive function support.
Scientific Evidence
- Hamblin MR 2016, Photochem Photobiol — Shining light on the head: Photobiomodulation for brain disorders
- Hennessy M & Hamblin MR 2017, J Opt — Photobiomodulation and the brain: a new paradigm
- Salehpour F et al. 2018, Front Neurosci — Brain photobiomodulation therapy: a narrative review
- Nizamutdinov D & Hamblin MR 2021, Aging Dis — Photobiomodulation for neurological conditions
Frequently Asked Questions
- Is photobiomodulation safe for everyone?
- It is generally very safe. Relative contraindications include pregnancy, application over active electronic implants, or suspected malignant lesions — all assessed during consultation before therapy.
- How many sessions are needed?
- Many patients notice improvement after 4–8 sessions. A typical programme is 2–3 times per week for 2–4 weeks, depending on the condition.
- Is this a harmful laser?
- No. PBM uses Class 3B lasers or medical LEDs at very low intensities — well below the threshold for tissue damage.
Wondering whether this modality is right for your condition?