Short answer: they are different treatments that happen to share the word "light". Narrowband UVB at 311nm is ultraviolet, it is a medical device treatment, and it is what dermatology departments use for psoriasis, vitiligo and atopic eczema. Red light therapy at 660 and 850nm contains no ultraviolet whatsoever and is used for skin appearance, recovery and general wellbeing — it is not a treatment for a diagnosed skin condition. If you have been diagnosed with psoriasis or vitiligo, the relevant device is a narrowband UVB lamp. If you have not, it almost certainly isn't.
We make both, which is unusual, and it is the reason we are careful to keep the two apart rather than blurring them into a single "light therapy" claim.
Where each sits on the spectrum
Visible light runs roughly 400 to 700 nanometres. Everything shorter than 400nm is ultraviolet. Everything longer than 700nm is infrared.
Narrowband UVB sits at 311nm — below visible light, invisible to the eye, and firmly in the ultraviolet range. It is the same family of light as sunburn and sunbeds, restricted to a narrow slice of it.
Red and near-infrared sit at roughly 600 to 1060nm — the far end of visible red and just beyond it. No ultraviolet is present at any point.
That gap is not a technicality. It determines what the light does to tissue, what the risks are, and what the device is for.
Side by side
| Narrowband UVB | Red / near-infrared | |
|---|---|---|
| Wavelength | 311nm | ~600–1060nm |
| Ultraviolet? | Yes | None |
| Visible? | No | Yes (the red is; near-infrared is not) |
| Used for | Psoriasis, vitiligo, atopic eczema | Skin appearance, recovery, wellbeing |
| Device class | Medical device | Wellness device |
| Eye protection | Required, every session | Advisable — the LEDs are bright |
| Exposure control | Strict. Timed, built up gradually | Flexible. Typically 5–20 minutes |
| Can it burn skin? | Yes, if overdosed | No — no UV involved |
| Medication interactions | Yes — photosensitising drugs matter | Not in the same way |
| Consumable parts | Tube, replaced periodically | LEDs, rated for tens of thousands of hours |
| Dermatologist involvement | Strongly advised | Not usually required |
What narrowband UVB is for
Narrowband UVB is the wavelength hospital dermatology departments use. It became the clinical standard from the 1980s onward because it removes the shorter UVB wavelengths — those below about 305nm — that cause reddening and burning without contributing to the therapeutic effect.
It is used for psoriasis, vitiligo and atopic eczema. Whether it is appropriate for you is a question for your doctor or dermatologist, not for a website.
A randomised trial published in the British Medical Journal compared UVB phototherapy delivered at home against the same treatment in an outpatient clinic, and concluded that home treatment was equally safe and equally effective, with a lower burden of treatment and greater patient satisfaction. Separately, research from the Department of Dermatology at Eberhard Karls University, Tuebingen, reported that its study did not provide evidence of increased skin cancer risk in patients treated with either broadband or narrowband UVB. Both papers are linked from our 1000MX product page.
The trade-off is that UVB carries genuine risk and has to be respected. Eye protection every session. Exposure times that start short and build gradually. Awareness of your skin type, because fairer skin reaches the same dose faster. And a check on any regular medication, because a number of common drugs — some antibiotics, diuretics, anti-inflammatories and retinoids among them — increase skin sensitivity to ultraviolet light.
What red light therapy is for
Red and near-infrared light works by a different mechanism entirely. Rather than the DNA and melanin effects that define ultraviolet exposure, it is studied for absorption by cytochrome c oxidase within the cell — a process called photobiomodulation.
It is used for skin appearance, post-exercise recovery, comfort in joints and muscles, and as part of an evening wind-down routine. There is a substantial research literature behind photobiomodulation, and we summarise individual studies elsewhere on this site with the source named each time.
What it is not: a treatment for psoriasis, vitiligo or eczema, and not something we offer as one. Be sceptical of any retailer promising a specific medical outcome from a red light panel — including us.
The practical differences are considerable. No ultraviolet means no burning risk and no cumulative exposure ceiling. Sessions are less regimented. The LEDs are bright enough that eye protection is sensible, but the consequence of getting the timing slightly wrong is nothing at all, where with UVB it is sore skin.
Can you use both?
Yes, and some people do — they are not in competition and they do not interfere with one another. A person managing psoriasis with a narrowband UVB lamp might separately use a red light panel for general recovery or skin appearance, in the same way they might use both a treadmill and a bicycle.
Two practical notes if you do. Keep them as separate sessions rather than stacking them back to back, so you can tell what is doing what. And if you are under specialist care, mention both to your dermatologist.
So which do you need?
Choose narrowband UVB if you have a diagnosed case of psoriasis, vitiligo or atopic eczema, you have discussed phototherapy with a doctor or dermatologist, and you want to treat it at home rather than travelling to a clinic several times a week. See the narrowband UVB range.
Choose red light if your interest is skin appearance, recovery after training, general comfort or an evening routine, and you do not have a diagnosed skin condition you are trying to treat. See the red light therapy panels, or the contact-free Halo LED for the face.
If you are unsure, the deciding question is simply whether a clinician has diagnosed you with something. If yes, talk to them before buying anything. If no, red light is the appropriate family of device.
And to be explicit about the thing people most often get wrong: a red light panel will not do the job of a narrowband UVB lamp. They are not stronger and weaker versions of the same treatment. Buying a red light panel to treat psoriasis is buying the wrong device.
Why we make both
Dermfix Ltd has been an ISO 13485 medical device manufacturer since 2009, and started with narrowband UVB. The red light range came later, built under the same quality system.
Most companies in this market sell one or the other. Wellness brands sell red light and have no medical device background; clinical suppliers sell UVB and have no consumer range. Making both means we have no commercial reason to blur the line — if you need UVB we would rather sell you UVB, and if you don't, we would rather not.
It also means the same measurement discipline applies to both. Every RLF panel publishes a spectrometer-measured output figure at a stated distance of 15cm, per model rather than one headline number across the range. Our UK red light panel buyer's guide explains why that matters and how most published irradiance figures are roughly double the honest one.
For the underlying physics of ultraviolet — how UVA, UVB and UVC differ, and why narrowband replaced broadband — see our guide to UVB phototherapy.
Common questions
Is red light therapy the same as UVB?
No. Red light therapy uses visible red and near-infrared wavelengths, roughly 600 to 1060nm, and emits no ultraviolet at all. Narrowband UVB is ultraviolet light at 311nm and is a medical device treatment. They are different treatments for different purposes.
Can red light therapy treat psoriasis?
Narrowband UVB at 311nm is the wavelength used in dermatology for psoriasis. Red light panels are not offered as a treatment for psoriasis or any other diagnosed condition. If you have psoriasis, speak to your dermatologist about phototherapy rather than substituting a red light panel for it.
Does red light therapy contain UV?
No. Red and near-infrared light sits at the opposite end of the spectrum from ultraviolet. A red light panel does not tan, does not burn, and carries none of the cumulative ultraviolet exposure considerations that apply to UVB.
Is a UVB lamp the same as a sunbed?
No. A sunbed emits mainly UVA for cosmetic tanning. A narrowband UVB lamp emits a narrow band around 311nm and is a medical device intended for treating specific skin conditions.
Can I use red light therapy and UVB together?
They do not interfere with one another and some people use both. Keep them as separate sessions rather than back to back, and tell your dermatologist if you are under specialist care.
Which is safer, red light or UVB?
Red light carries no ultraviolet and therefore none of the burning or cumulative exposure risk. UVB carries genuine risk and requires eye protection, controlled exposure times and awareness of skin type and medication. But they treat different things, so safety is not the deciding factor — suitability is.
Do I need a prescription for a narrowband UVB lamp in the UK?
Home phototherapy devices can be purchased directly. That said, if you are under specialist care for psoriasis, vitiligo or eczema, tell your dermatologist you intend to use one. Home treatment works alongside medical supervision, not instead of it.
This article is general information about the difference between two types of device. It is not medical advice and is not a substitute for the guidance of your doctor or dermatologist. Always follow the instructions supplied with your device.