In short. Pigment and redness are the two commonest complaints and they are different targets. Why one general setting treats both badly, and how the two are sequenced.
Key points
- Before each session, you should be able to say what is being treated in it and what is being left alone.
- A plan that answers only that the face is being treated has not distinguished between the two complaints, and the sessions that follow tend to be spent adjusting rather than progressing.
Two complaints bring most people to a light-treatment consultation, and they are usually mentioned in the same sentence: the brown patches, and the redness. They look like one problem and they are not. Colour in the skin comes from two different sources, and the two absorb light differently, respond to different settings, and behave differently afterwards.
Two targets, not one
Brown colour is pigment produced by the skin's own cells. Red colour is haemoglobin inside blood vessels, seen through the skin. A setting chosen to act on one of them is not the setting that suits the other, and the depth at which each sits differs too. This is why the word used to describe the complaint matters less than which of the two is being treated in a given pass.
Why one general setting does both badly
A broadband source can act on both because it carries a band that both targets absorb. That is not the same as treating both well. The energy that suits pigment is not the energy that suits vessels, and a plan that tries to do both in one pass derives a compromise for each. In practice the two are sequenced: one target is treated for a period, then the other.
Ask which target is being treated today
Before each session, you should be able to say what is being treated in it and what is being left alone. A plan that answers only that the face is being treated has not distinguished between the two complaints, and the sessions that follow tend to be spent adjusting rather than progressing.
What the two do afterwards
Pigment that has been treated darkens and flakes, the area looks more even for a period, and sun exposure brings new pigment back. Redness behaves differently: it settles after each session and returns in response to heat, emotion, alcohol and the condition driving it, which continues its own course whatever is done to the vessels.
The case that is treated differently
Pigment driven by hormones rather than by sun is assessed as its own problem. It responds unpredictably to heat and to light, and it can darken after a treatment that would have helped a sun spot. That is a reason for a different plan, and sometimes for no light treatment at all.
Three things to have answered before a course
- Which of the two is being treated first, and how the plan separates them rather than treating both at once.
- Whether any of the pigment is hormonal, because that changes the plan and sometimes cancels it.
- What happens when the redness returns, since it usually does, and whether that is a maintenance rhythm or a new course.
Separating the two complaints is the work of the assessment, and treating them as one is what a general setting does.
Frequently asked questions
Can one session treat both the brown patches and the redness?
Sometimes the same pass acts on both, because a broadband source carries a band that both targets absorb. What it cannot do is deliver the amount of energy that suits each. A plan that treats both with one setting is usually a compromise for both, which is why many plans treat one target for a period and then the other.
Why does redness come back more readily than pigment?
Because what drives it is usually still present. Sun damage accumulates from exposure, but flushing responds to heat, emotion, alcohol and the condition behind it, and that condition continues its own course. Treated vessels can recur while the tendency that produced them remains, so redness is often managed in a rhythm rather than finished.
Is hormonal pigment treated the same way as sun spots?
No, and this is the one place where a light plan can make things worse. Pigment driven by hormones responds unpredictably to heat and light and can darken after treatment. It is assessed as its own problem, and a plan built for sun damage is not the plan for it.
Risks & Limitations
- No result can be guaranteed, and how much pigment or redness changes varies between people.
- Treated skin can be left darker or lighter than it was. That change may fade over months, or only partly.
- Too much energy for the skin can burn it, and a burn can blister and scar.
- Pigment and redness recur. Sun exposure, hormonal change and the condition behind the redness all bring them back, so maintenance sessions and sun protection are part of the result.
- Treatment can wake a cold sore in someone with a history of them, and both light sources require eye protection.
When to Seek Care
- Blistering, an open area, or pain that is worsening rather than settling after a session.
- Pigment that is spreading or deepening well after the treated area should have settled.
- A cold sore outbreak that spreads beyond its usual area, or skin that is hot, spreading and painful.
- A mole or mark that is new, changing, bleeding or itching — have it examined rather than treated.
- Eye pain or any change in vision after treatment — seek care the same day.
References & Further Reading
- American Academy of Dermatology (AAD) — skin and light treatment guidance
- American Society of Plastic Surgeons (ASPS) — procedure and safety guidance
- National Institute for Health and Care Excellence (NICE, UK) — relevant guidance
- Cochrane Library — systematic reviews
- Chinese Medical Association Plastic Surgery Branch — clinical guidance
This page is patient education, not medical advice, and it does not cite individual studies. Discuss your own case with a qualified clinician. To arrange an assessment at Chongqing West District Hospital, see Contact & Consultation.