Lasers Med Sci. 2016 Jul 20. [Epub ahead of print]

Transcranial low-level infrared laser irradiation ameliorates depression induced by reserpine in rats.

Mohammed HS1.

Author information

  • 1Biophysics Department, Faculty of Science, Cairo University, Giza, Egypt.


Transcranial low-level infrared laser is a modality of therapy based on the principle of photons delivered in a non-invasive manner through the skull for the treatment of some neurological conditions such as psychological disorders, traumatic brain injuries, and neurodegenerative diseases among others. In the present study, effects of low-level infrared laser irradiation with different radiation powers (80, 200, and 400 mW, continuous wave) were investigated on normal animals subjected to forced swimming test (FST). Results indicated that there are changes in FST parameters in animals irradiated with laser; the lowest dose provoked a significant increase in animal activity (swimming and climbing) and a significant decrease in animal’s immobility, while the highest laser dose resulted in a complete inverse action by significantly increasing animal immobility and significantly decreasing animal activity with respect to control animals. The lowest dose (80 mW) of transcranial laser irradiation has then utilized on animals injected with a chronic dose of reserpine (0.2 mg/kg i.p. for 14 days) served as an animal model of depression. Laser irradiation has successfully ameliorated depression induced by reserpine as indicated by FST parameters and electrocorticography (ECoG) spectral analysis in irradiated animals. The findings of the present study emphasized the beneficial effects of low-level infrared laser irradiation on normal and healthy animals. Additionally, it indicated the potential antidepressant activity of the low dose of infrared laser irradiation.

Neurophotonics. 2016 Jul;3(3):031404. doi: 10.1117/1.NPh.3.3.031404. Epub 2016 Mar 4.

Review of transcranial photobiomodulation for major depressive disorder: targeting brain metabolism, inflammation, oxidative stress, and neurogenesis.

Cassano P1, Petrie SR2, Hamblin MR3, Henderson TA4, Iosifescu DV5.

Author information

  • 1Massachusetts General Hospital, Depression Clinical and Research Program, One Bowdoin Square, 6th Floor, Boston, Massachusetts 02114, United States; Harvard Medical School, Department of Psychiatry, 401 Park Drive, Boston, Massachusetts 02215, United States.
  • 2Massachusetts General Hospital, Depression Clinical and Research Program, One Bowdoin Square, 6th Floor, Boston, Massachusetts 02114, United States.
  • 3Massachusetts General Hospital, Wellman Center for Photomedicine, 50 Blossom Street, Boston, Massachusetts 02114, United States; Harvard Medical School, Department of Dermatology, 55 Fruit Street, Boston, Massachusetts 02114, United States; Harvard-MIT Division of Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
  • 4Synaptic Space, 3979 East Arapahoe Road, Littleton, Colorado 80122, United States; Neuro-Laser Foundation, Suite 420, 215 South Wadsworth, Lakewood, Colorado 80226, United States.
  • 5Mount Sinai Medical School, Mood and Anxiety Disorders Program, 1428 Madison Avenue, New York, New York 10029, United States; Mount Sinai Medical School, Department of Psychiatry and Neuroscience, 1 Gustave L. Levy Place, New York, New York 10029, United States.


We examined the use of near-infrared and red radiation (photobiomodulation, PBM) for treating major depressive disorder (MDD). While still experimental, preliminary data on the use of PBM for brain disorders are promising. PBM is low-cost with potential for wide dissemination; further research on PBM is sorely needed. We found clinical and preclinical studies via PubMed search (2015), using the following keywords: “near-infrared radiation,” “NIR,” “low-level light therapy,” “low-level laser therapy,” or “LLLT” plus “depression.” We chose clinically focused studies and excluded studies involving near-infrared spectroscopy. In addition, we used PubMed to find articles that examine the link between PBM and relevant biological processes including metabolism, inflammation, oxidative stress, and neurogenesis. Studies suggest the processes aforementioned are potentially effective targets for PBM to treat depression. There is also clinical preliminary evidence suggesting the efficacy of PBM in treating MDD, and comorbid anxiety disorders, suicidal ideation, and traumatic brain injury. Based on the data collected to date, PBM appears to be a promising treatment for depression that is safe and well-tolerated. However, large randomized controlled trials are still needed to establish the safety and effectiveness of this new treatment for MDD.


Behavioral and Brain Functions 2009, 5:46doi:10.1186/1744-9081-5-46


Psychological benefits 2 and 4 weeks after a single treatment with near infrared light to the forehead: A pilot study of 10 patients with major depression and anxiety

Fredric Schiffer , Andrea L Johnston , Caitlin Ravichandran , Ann Polcari , Martin H Teicher , Robert H Webb and Michael R Hamblin

Published 8 December 2009

Abstract (provisional)


Many studies have reported beneficial effects from the application of near-infrared (NIR) light photobiomodulation (PBM) to the body, and one group has reported beneficial effects applying it to the brain in stroke patients. We have reported that the measurement of a patient’s left and right hemispheric emotional valence (HEV) may clarify data and guide lateralized treatments. We sought to test whether a NIR treatment could 1. improve the psychological status of patients, 2. show a relationship between immediate psychological improvements when HEV was taken into account, and 3. show an increase in frontal pole regional cerebral blood flow (rCBF), and 4. be applied without side effects.


We gave 10 patients, (5M/5F) with major depression, including 9 with anxiety, 7 with a past history of substance abuse (6 with an opiate abuse and 1 with an alcohol abuse history), and 3 with post traumatic stress disorder, a baseline standard diagnostic interview, a Hamilton Depression Rating Scale (HAM-D), a Hamilton Anxiety Rating Scale (HAM-A), and a Positive and Negative Affect Scale (PANAS). We then gave four 4-minute treatments in a random order: NIR to left forehead at F3, to right forehead at F4, and placebo treatments (light off) at the same sites. Immediately following each treatment we repeated the PANAS, and at 2-weeks and at 4-weeks post treatment we repeated all 3 rating scales. During all treatments we recorded total hemoglobin (cHb), as a measure of rCBF with a commercial NIR spectroscopy device over the left and the right frontal poles of the brain.


At 2-weeks post treatment 6 of 10 patients had a remission (a score less than or equal to 10) on the HAM-D and 7 of 10 achieved this on the HAM-A. Patients experienced highly significant reductions in both HAM-D and HAM-A scores following treatment, with the greatest reductions occurring at 2 weeks. Mean rCBF across hemispheres increased from 0.011 units in the off condition to 0.043 units in the on condition, for a difference of 0.032 (95% CI: -0.016, 0.080) units, though this result did not reach statistical significance. Immediately after treatment the PANAS improved to a significantly greater extent with NIR “on” relative to NIR “off” when a hemisphere with more positive HEV was treated than when one with more negative HEV was treated. We observed no side effects.


This small feasibility study suggests that NIR-PBM may have utility for the treatment of depression and other psychiatric disorders and that double blind randomized placebo-controlled trials are indicated. Trial registration Identifier: NCT00961454

Vopr Kurortol Fizioter Lech Fiz Kult. 2008 Jul-Aug;(4):24-6.

Low-intensity laser irradiation in the combined treatment of depressive disorders in patients with chronic salpingo-oophoritis

[Article in Russian]

Mamedov FM.

This study was designed to evaluate the possibility to use low-intensity laser radiation in combined therapy of somatogenic depressions in patients having gynecological problems, such as inflammatory disease of uterine appendages. It was shown that the combined treatment including administration of antidepressants significantly accelerated the development of beneficial changes and stabilized depressive manifestations. Inclusion of low-intensity laser irradiation in the combined therapy further improved its positive effect. Nevertheless, the complete recovery could not be achieved in the absence of specific antidepressant treatment despite the alleviation of depressive symptoms.

Prog Neuropsychopharmacol Biol Psychiatry.  2007 Oct 1;31(7):1397-400. Epub 2007 Jun 19.

Infrared irradiation has potential antidepressant effect.

Tsai JF, Hsiao S, Wang SY.


Department of Psychiatry, Buddhist Tzu-Chi General Hospital, Hualien, Taiwan.



Light therapy was only partially effective in treatment of depression when compared with summer’s sunlight. The antidepressant effect of infrared irradiation was evaluated using an experimental animal model.


Seventeen mice were randomly assigned to the exposure group (n = 9) and the control group (n = 8). The mice in the exposure group received infrared irradiation for 60 min daily during the study period of 4 weeks. The two groups were given forced swim test once a week to evaluate depression with the measurement of the immobility time.


We found that the exposure group showed a tendency of less immobility time by the end of the 3rd week when compared with the control group, and at the end of 4th week the difference reached a statistical significance (t(15) = 2.873; p = 0.012).


The result indicates that the immobility time in forced swim test, the sign of depression, can be reduced after prolonged (4 weeks) exposure to infrared irradiation in the animal model. The result suggests that a continuous application of infrared irradiation has antidepressant effect.

Acupunct Med. 2005 Sep;23(3):103-11.

Laser acupuncture for mild to moderate depression in a primary care setting–a randomised controlled trial.

Quah-Smith JI, Tang WM, Russell J.

Monash University, Victoria, Australia.

OBJECTIVE: Depression is a major public health problem. There is some evidence supporting the effectiveness of needle acupuncture in its treatment. Laser stimulation, regarded here as a modality of acupuncture, is non-invasive and therefore free of infection risk; and it is acceptable to patients with needle phobia. The technique is relatively easily learned by community-based general practitioners. It is also amenable to sham control and therefore double-blinding in clinical trials. A double-blind randomised controlled trial was conducted to test the efficacy of low level laser acupuncture in mild to moderate depression.

METHODS: Thirty patients with depression were randomised to receive either active or inactive laser treatment. The laser unit could be switched to one of two settings. One switch position delivered active laser acupuncture and the other was inactive (sham). In the active mode, 0.5J was delivered to each of six to eight individually tailored acupuncture sites per visit. All patients were treated twice weekly for four weeks then weekly for a further four weeks. The patients and the acupuncturist were both blinded to conditions. Outcome was assessed using the Beck Depression Inventory at baseline, weeks four and eight during treatment, and at 4 and 12 weeks following the treatment.

RESULTS: At the end of the treatment period, Beck Depression Inventory scores fell from baseline by 16.1 points in the intervention group and by 6.8 points in the sham control group (P<0.001). The difference showed only a trend four weeks later, but was again significant after 12 weeks (P=0.007). Laser acupuncture was well tolerated with transient fatigue as the most common adverse effect.

CONCLUSION: Laser acupuncture may be worth further investigation as a treatment for mild to moderate depression in primary care.

Lasers Med Sci. 2004;19(2):100-4.

Use of low-energy laser as adjunct treatment of alcohol addiction.

Zalewska-Kaszubska J, Obzejta D.

Department of Pharmacodynamics, Medical University, Muszynskiego 1, 90-151 Lodz,

Auricular acupuncture is a medical method that has been used in the treatment of alcohol addiction. In our study we decided to intensify this method by additional biostimulation of the whole organism. The aim of this study was the therapy of patients with alcohol dependence syndrome. Fifty-three alcoholics were treated with two types of laser stimulation in four sessions. Each session consisted of 20 consecutive daily helium-neon laser neck biostimulations and 10 auricular acupuncture treatments with argon laser (every 2nd day). The Beck Depression Inventory-Fast Screen (BDI-FS) was used to assess their frame of mind before the session and after 2 months of treatment. Moreover, beta-endorphin plasma concentration was estimated five times using the radioimmunoassay (RIA) method. Improvement in BDI-FS and increase in, beta-endorphin level were observed. These results suggest that laser therapy can be useful as an adjunct treatment for alcoholism.