Q-Switched Laser

A Q-switched laser breaks up skin pigment and tattoo ink with extremely short, powerful pulses lasting billionths of a second. It is used for sun and age spots, freckles, some birthmarks and tattoo removal. Because little heat reaches the surrounding tissue, recovery is short. The number of sessions depends on the type of spot and varies from person to person, and treatment is planned after a medical examination.

What is a Q-switched laser and how does it work?

Q-switching is a technology that stores laser energy and releases it as a single powerful pulse within nanoseconds; “Q-switched laser” is the general name for devices that work this way.

The pulse is so short that the energy shatters the target pigment or ink particle into tiny fragments before it can spread as heat. The effect therefore stays largely confined to the target and the surrounding tissue is less affected. The body’s clearing system removes the fragmented pigment over the following weeks, which is why results appear gradually rather than all at once.

Q-switched lasers can work at different wavelengths. A deeper-reaching wavelength is chosen for deep pigment and dark tattoo ink, and a more superficial one for surface spots and some coloured inks. The choice depends on the depth and colour of the spot and on your skin type.

What does a Q-switched laser treat?

A Q-switched laser is used for spots caused by excess pigment in the skin and for tattoo removal.

• Sun and age spots: Brown spots that appear over time on sun-exposed areas. For general advice, see our article on how to get rid of sun spots.
• Freckles: They can fade noticeably but may darken again with sun exposure.
• Some birthmarks: Pigment lesions such as café-au-lait spots and naevus of Ota. Response varies from lesion to lesion; some need many sessions and some may return over time.
• Tattoo removal: Dark and black inks respond better; coloured tattoos need more sessions. See our tattoo removal page for details.
• Carbon peeling: A carbon layer applied to the skin is removed with the Q-switched laser for a superficial renewal; see carbon peeling.

Not every spot is treated with a laser. For hormonal pigmentation such as melasma, a laser on its own is not the first choice and can darken the patches in some people. Moles and any spot that changes in shape, colour or size must be examined before laser treatment. We explain which method suits which spot on our pigmentation treatment page.

How is Q-switched laser treatment done?

Treatment is carried out after an examination and assessment of the spot, with eye protection in place, and takes 10–30 minutes depending on the area.

• Examination: The doctor assesses the type and depth of the spot and your skin type; any suspicious-looking spot is examined separately before laser treatment.
• Preparation: The skin is cleansed and a numbing cream is applied if needed. Both your eyes and the operator’s are protected with laser-safe glasses.
• Treatment: The laser pulses feel like a rubber band snap or a brief crackle. Tattoo removal is usually more uncomfortable than spot treatment.
• Straight afterwards: The area becomes red and slightly swollen; tattoos show brief whitening. Cooling helps.

At our clinic in Etiler, Q-switched laser treatments are planned under a doctor’s supervision after the spot and skin have been assessed.

How many sessions does a Q-switched laser take?

The number of sessions depends on the type and depth of the spot and varies from person to person; superficial spots usually need 1–3 sessions, while deep spots and tattoos need more.

• Sun and age spots: Often 1–3 sessions.
• Deep pigment spots: Lesions such as naevus of Ota may need many sessions over a long period.
• Tattoos: Usually 3–10 sessions, depending on colour, depth and density.

Between sessions, usually 4–8 weeks are left for the skin to heal and the fragmented pigment to clear, and 6–8 weeks for tattoo removal. Trying to get fast results with high energy in a single session increases the risk of scarring and colour change.

What should you do after Q-switched laser treatment?

The most important rules after treatment are to protect the skin from the sun and not to pick at the thin crusts that form.

• Spots may darken in the first days and form a thin crust, which usually falls off on its own within 1–2 weeks.
• Do not pick the crusts or rub the area.
• Use a broad-spectrum, high-factor sunscreen every day; avoid direct sun, sunbeds and tanning.
• Use the soothing cream your doctor recommends, and pause peels, retinoids and irritating products for a few days.
• If blisters form after tattoo removal, do not burst them; use the dressing your doctor recommends.

Treatment can be done in any season, but if you will not be able to protect your skin from the sun afterwards, for example just before a holiday, it is better to postpone the session.

What are the side effects and risks of a Q-switched laser?

Side effects of a Q-switched laser are mostly temporary; the main risk is a change in skin colour, seen especially in darker and sun-exposed skin.

• Common: Redness, slight swelling, tenderness and thin crusting; with tattoos, whitening and tiny pinpoint bleeding.
• Colour change: The area may end up darker or lighter than the surrounding skin. This usually settles within months but can occasionally last longer.
• Blisters and scarring: These can occur especially with tattoo removal and high-energy treatments; the risk of scarring increases if aftercare is not followed.
• Permanent make-up and some coloured inks: Skin-tone, white or red-toned inks can darken with laser treatment, so a small test area may be recommended first.
• Eye injury: Without suitable protective glasses there is a serious risk, so eye protection is mandatory at every session.

A spot will not always disappear completely, and a tattoo cannot always be removed without a trace; the result depends on the type of spot and how your skin responds.

Who should not have it, and when should you see a doctor?

Recently tanned skin, an active infection in the area and undiagnosed suspicious spots are the main reasons not to have Q-switched laser treatment.

• Freshly tanned or sunburnt skin
• An active infection, cold sore or open wound in the treatment area
• Moles or undiagnosed spots that change in shape, colour or size
• Pregnancy (cosmetic treatments are usually postponed)
• A tendency to keloids or poor scarring
• Use of medicines that cause light sensitivity, or recent use of the acne medicine isotretinoin (always tell your doctor)

If after treatment you notice signs of infection such as increasing pain, discharge, spreading redness or fever, contact your doctor.

Frequently asked questions

What is a Q-switched laser?

A Q-switched laser delivers its energy in very short, powerful pulses lasting nanoseconds. These pulses break skin pigment and tattoo ink into tiny fragments, which the body then clears over the following weeks.

What does a Q-switched laser treat?

It is used for sun and age spots, freckles, some pigment lesions such as café-au-lait spots and naevus of Ota, and tattoo removal. It is also used in carbon peeling treatments.

Does a Q-switched laser hurt?

The pulses feel like a brief rubber band snap. Spot treatment is usually well tolerated; tattoo removal can be more uncomfortable, so numbing cream and cooling are used if needed.

Does a Q-switched laser leave scars?

Permanent scarring is rare when the right energy is used and aftercare is followed. Temporary colour changes can occur and usually settle within months; not picking crusts and protecting the skin from the sun reduce the risk.

Do spots come back after Q-switched laser treatment?

Sun spots and freckles can form again in the same area if the skin is not protected from the sun. Some birthmarks may also return over time. Regular sun protection is the most important factor in maintaining the result.

What is the difference between a Q-switched and a picosecond laser?

Both are short-pulse lasers that break up pigment; picosecond lasers use even shorter pulses. Your doctor decides which laser is suitable based on the type of spot or tattoo.

This content is for information only and does not replace a medical examination. To have your spot assessed, get in touch with us.