Red Light Therapy Dose Guide
More is not always better. Understand the biphasic dose response (Arndt-Schulz curve) and find your optimal dose range.
The Biphasic Dose Response
Arndt-Schulz Curve | Dosing in J/cm²
Biological Response vs. Dose
Dose Zones Explained
Sub-Therapeutic
< 3 J/cm²Too little energy to trigger meaningful biological effects. Common with underpowered devices or very short sessions.
Optimal
3 - 50 J/cm²The therapeutic sweet spot. Most clinical studies show positive outcomes in this range. Stimulates mitochondrial activity and cellular repair without overwhelming the system.
Diminishing Returns
50 - 100 J/cm²Benefits plateau and begin to decline. Extra energy does not proportionally increase results. Longer sessions waste time without added benefit.
Inhibitory
> 100 J/cm²Excessive dose that can inhibit cellular function and potentially cause harm. The biphasic response flips: stimulation becomes suppression.
At a Glance
Quick Reference by Condition Type
| Condition | Dose Range | Notes |
|---|---|---|
| Skin (surface) | 3 - 15 J/cm² | Acne, wrinkles, wound healing |
| Pain / Inflammation | 10 - 30 J/cm² | Arthritis, tendinitis, muscle soreness |
| Deep tissue | 20 - 50 J/cm² | Joint repair, bone healing, nerve recovery |
| Hair regrowth | 4 - 10 J/cm² | Androgenetic alopecia, scalp health |
| Muscle recovery | 10 - 40 J/cm² | Post-exercise, DOMS, performance |
Key Insight
The biphasic dose response (Arndt-Schulz principle) means more light is not always better. A dose of 10 J/cm² can stimulate healing while 200 J/cm² to the same area can inhibit it. Use the Dose Calculator to find your exact session time.
redlightos.com/infographics/dose-guide
Related Resources
Dose Calculator
Enter your device specs and get a personalized session time.
Dosing Guide
Complete guide to dosing theory, the biphasic curve, and condition-specific protocols.
Wavelength Chart
See penetration depths for each wavelength to understand which dose applies where.
Getting Started Guide
New to red light therapy? Start here with our 5-step visual guide.
Medical Disclaimer: This content is for informational and educational purposes only. It is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Red light therapy devices are wellness devices and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary.