The following message I had posted to other topic, sincerely wish to be helpful.
The conclusion of documented clinical reports for hair loss treatments to be effective include alopecia areata and male pattern alopecia as followings:
1) Recommended dosage: 3~6 J/cm2
2) Treatment frequency: 2~3 times/week
You must carefully calculate the total dosage irradiated from your LLLT device by the following formulas:
Power Density(I) I(W/cm²)=P(mW)/1000 /A(cm²)/d(cm)
P : Laser power output
A : Treated area (laser spot size)
d : Distance between laser device and target tissue
Calculated Treatment Time(Tc) Tc(second)=D(J/cm²) x A/P x 1000 x d
D : Dosage
For example: If you use a LLLT LaserComb with
1) laser beam power output 5 mW,
2) laser spot radius 2 mm
3) Estimated distance between laser comb and follicle 1.4 cm(follicle depth 0.4 cm, comb-scalp distance 1 cm)
P= 5 mW
A= 0.2 cm x 0.2 cm x 3.14= 0.125 cm²
Tc= 6 x 0.125 / 5 x 1000 x 1.4 = 210 (second)
Mathematic Meaning:
You must take 210 seconds to treat 0.125 cm² of your scalp to reach the target dosage of 6 J/cm²
If you use your laser comb/brush with the above specifications for 10 or 15 minutes to treat the whole scalp, the dosage is very very small:
For example: If you use laser comb as the instruction from the manufacturer- treat 4 second and move
Actual Dosage (Da) Da=P x Tc/D/1000/d
= 5 x 4/0.125/1000/1.4
= 0.114 (J/cm²)
The dosage is less than 1/50 of recommended dosage.
My recommendation:
1) Treat longer time on your target area (baldness) if you can stand the trouble of holding
2) Don't worry about the side effect of LLLT. Laser beam in the range of visible red (600~700nm) or infrared (700~1000nm) is natural light with monochrome and coherent characteristics. There are more 2,500 clinical reports of LLLT, effective or not, no any report about side effect.
There are some valuable information regard LLLT frequently asked questions a:
http://www.konftec.com/html/ko_faq.html