What Is Laser Hair Removal?
Laser hair removal is a light-based treatment designed to reduce unwanted hair over the long term. The laser delivers a specific wavelength of light that is absorbed by melanin in the hair and converted into heat, which affects the hair follicle and reduces its ability to produce new hair.
The more accurate term is permanent hair reduction rather than permanent removal of every single hair. After a treatment course, hair typically grows back more slowly, becomes finer, and decreases in density, although some regrowth may occur over time.
How Does Laser Hair Removal Work?
Laser hair removal is based on a principle called selective photothermolysis. The goal is to deliver enough light energy to the pigment in the hair while limiting unnecessary heat exposure to the surrounding skin.
For this reason, treatment effectiveness and safety depend on several factors, including skin tone, hair colour, hair thickness, wavelength, fluence, pulse duration and cooling. The same laser settings should not be used for every patient.
Is Laser Hair Removal Permanent?
Laser treatment can provide long-term reduction in hair growth, but it does not guarantee that every hair will disappear permanently for life.
The U.S. FDA defines permanent hair reduction as a long-term, stable decrease in the number of hairs that regrow after completing a treatment regimen.
Some hair may return due to factors such as hormones, age, genetics, treatment area or conditions such as PCOS. Maintenance sessions may therefore be useful for some patients.
What Is Primelase Excellence?
Primelase Excellence is the laser platform used for hair reduction treatments at Smooth Clinic. It is a high-powered diode laser system with multiple wavelength handpieces that allow treatment settings to be adapted to different skin tones and hair characteristics.
Primelase Excellence includes several wavelength options:
- Alex: 755 nm
- Diode: 810 nm
- Blend: 810 + 940 + 1060 nm
- YAG: 1060 nm
The manufacturer describes the 810 nm Diode handpiece as suitable for permanent hair reduction across Fitzpatrick skin types I–VI, while the Blend handpiece combines 810, 940 and 1060 nm wavelengths and is designed to provide greater flexibility across different skin conditions, including tanned skin.
The platform also uses contact cooling technology to help manage surface temperature and improve comfort during treatment.
What Types of Laser Hair Removal Are Available?
Several laser and light technologies can be used for hair reduction. They differ mainly in wavelength, melanin absorption and depth of penetration.
| Technology | Typical Wavelength | What to Know |
|---|---|---|
| Alexandrite | 755 nm | High melanin absorption and commonly used for darker hair on lighter skin types |
| Diode Laser | Around 800–810 nm | Offers a balance between melanin targeting and penetration depth and can be used across multiple skin types with appropriate settings |
| Nd:YAG | 1064 nm | Lower melanin absorption in the epidermis makes longer wavelengths useful when treating darker skin types |
| IPL | Broad-spectrum light | Can be used for hair reduction but is not a single-wavelength laser |
Diode vs Alexandrite vs Nd:YAG: Which Is Better?
There is no single laser that is best for every patient. The right choice depends on skin phototype, hair colour, hair thickness and the treatment settings used.
Research in patients with skin of colour shows that Alexandrite, Diode, Nd:YAG and IPL can all reduce unwanted hair when appropriate protocols are used. However, darker skin contains more epidermal melanin, so wavelength selection and conservative settings become particularly important to reduce the risk of burns and pigment changes.
How Is Primelase Excellence Different from a Standard Diode Laser?
“Diode Laser” describes a type of laser technology, but not every diode laser system has the same specifications.
Features of Primelase Excellence include:
- Multiple wavelength handpieces for different skin and hair characteristics
- 810 nm Diode for permanent hair reduction across different phototypes
- Blend 810 + 940 + 1060 nm for flexible treatment planning
- Ultra Short Pulse technology for pulse delivery
- Contact cooling to help protect the skin surface and improve comfort
- Static and Dynamic treatment modes
However, a more powerful device does not automatically guarantee a better result. Correct treatment parameters and matching the settings to the patient’s skin and hair remain essential.
Who Is Laser Hair Removal Suitable For?
Laser hair removal may be useful if you want to reduce unwanted hair and the need for frequent shaving, waxing or plucking.
- You shave frequently and want longer-lasting hair reduction
- You develop ingrown hairs after shaving or waxing
- You experience razor bumps or shaving irritation
- You want to reduce hair on the underarms, legs, arms, chest, back or bikini area
- You want to reduce beard or facial hair density
- You have pseudofolliculitis barbae associated with ingrown beard hairs
If underarm hair is your main concern, you can read our dedicated Underarm Laser Hair Removal Guide for more information about treatment, preparation and aftercare.
Which Hair Colours Respond Best to Laser?
Because laser hair removal targets melanin, dark, pigmented hairs generally respond better than very light hairs.
White, grey, very light blonde and some red hairs contain little melanin and may respond poorly to conventional laser hair removal.
Can People with Dark Skin Have Laser Hair Removal?
Yes. Laser hair reduction can be performed on darker skin when the wavelength, fluence, pulse duration and cooling are selected appropriately.
Because darker skin contains more melanin in the epidermis, inappropriate settings can increase the risk of burns, post-inflammatory hyperpigmentation or hypopigmentation.
Skin phototype should therefore be assessed before treatment rather than using identical settings for every patient.
Can I Have Laser Hair Removal If I Have PCOS?
Laser treatment can reduce existing unwanted hair in patients with hormonal conditions such as PCOS, but it does not treat the underlying hormonal cause.
Patients with hormone-related hair growth may require additional sessions or maintenance treatment and should discuss the underlying condition with an appropriate medical professional.
Which Areas Can Be Treated?
Laser hair removal can be performed on many facial and body areas when the skin is suitable for treatment.
| Area | Common Reason for Treatment |
|---|---|
| Underarms | Reduce hair, stubble and shaving-related ingrown hairs |
| Upper Lip / Beard / Chin | Reduce frequent shaving, razor irritation and facial hair density |
| Arms | Long-term reduction in hair density |
| Legs | Reduce the need for regular shaving or waxing |
| Chest / Abdomen | Reduce coarse or dense body hair |
| Back | Reduce hair over a large area that is difficult to manage at home |
| Bikini | Reduce hair around the bikini line |
| Brazilian | More extensive hair reduction in the intimate area according to the selected treatment zone |
Can Laser Hair Removal Help with Ingrown Hairs?
Yes, when ingrown hairs are related to shaving, plucking or hairs growing back into the skin.
Reducing the number and thickness of hairs can reduce repeated irritation and the chance of hairs becoming trapped beneath the skin.
The FDA 510(k) indications for Primelase Excellence also include treatment of pseudofolliculitis barbae, a condition commonly associated with ingrown beard hairs.
However, not every bump around a hair follicle is caused by an ingrown hair. Persistent inflammation should be assessed to rule out other skin conditions.
Does Laser Hair Removal Make Skin Lighter?
Laser hair removal is not primarily a skin-whitening treatment.
The skin may appear smoother after hair reduction, and reducing repeated shaving, friction and ingrown-hair inflammation may indirectly improve the appearance of some dark marks over time.
However, patients should not expect hair-removal laser to directly lighten their natural skin colour.
How Many Laser Hair Removal Sessions Do I Need?
Laser hair removal requires multiple sessions because not all hairs are in the same stage of the growth cycle at the same time.
Laser is most effective when hair is in the anagen or active growth phase. Repeated sessions are therefore required to target additional hairs as they enter a responsive stage.
The American Academy of Dermatology notes that patients commonly need approximately six or more treatments, although the actual number varies.
Factors include:
- Treatment area
- Hair colour and thickness
- Skin phototype
- Hormonal factors
- Laser technology and settings
- Individual response
For this reason, no clinic should assume that the same number of sessions will be enough for every patient.
How Often Should Laser Hair Removal Be Done?
Treatment intervals should follow the hair-growth cycle of the area being treated.
Sessions may initially be spaced around 4–6 weeks apart, but the ideal interval can change depending on the body area and how quickly new hair becomes visible.
Facial hair and body hair do not necessarily follow the same growth pattern, so treatment intervals may be adjusted during the course.
Will I See Results After the First Session?
Some treated hairs begin to shed after the first session, and you may notice that hair grows back more slowly or appears less dense.
However, the first session cannot treat every hair follicle effectively because only a proportion of hairs are in the appropriate growth phase at any one time.
Results therefore become more noticeable as treatment sessions accumulate.
How Should I Prepare Before Laser Hair Removal?
- Avoid plucking or waxing before treatment because the hair follicle needs to remain present as a target for the laser.
- Shaving is usually allowed and may be recommended before treatment according to clinic instructions.
- Avoid tanning and excessive sun exposure because increased epidermal melanin can raise the risk of laser-related skin reactions.
- Tell the provider about medications and skincare products, especially anything that may increase photosensitivity.
- Report previous burns, blisters or pigment changes following laser treatment.
- Tell the clinic if you have an active rash, wound or infection in the treatment area.
What Happens During Laser Hair Removal?
- Skin and Hair Assessment – Skin tone, hair colour, density and thickness are evaluated.
- Skin Check – The treatment area is checked for tanning, inflammation, wounds or other contraindications.
- Area Preparation – The skin is cleaned and hair is prepared according to protocol.
- Laser Settings – Wavelength, fluence, pulse duration and treatment mode are adjusted.
- Laser Treatment – Energy is delivered across the treatment area while cooling helps manage surface temperature.
- Post-Treatment Assessment – The skin response is checked and aftercare instructions are provided.
Treatment time depends on the size of the area. Small areas such as the underarms usually require less time than full legs or the back.
Does Laser Hair Removal Hurt?
Sensation varies according to the treatment area, hair density, energy settings and individual pain sensitivity.
Patients may feel warmth, a brief snapping sensation or short pulses of heat, particularly in areas with dense or coarse hair.
Primelase Excellence uses contact cooling to help manage skin temperature and improve comfort, but it would not be realistic to promise that the treatment is completely painless for every patient.
What Should I Do After Laser Hair Removal?
- Avoid aggressive rubbing, scratching or exfoliation while the skin is sensitive.
- Use a gentle moisturiser if the skin feels dry or tight.
- Use broad-spectrum sunscreen on exposed treatment areas.
- Limit strong sun exposure while redness or sensitivity remains.
- Avoid irritating skincare products until the skin has recovered.
- Do not pluck or wax between sessions because this removes the laser target from the follicle.
If you develop blistering, a significant burn, prolonged pain or marked pigment changes, contact the clinic for assessment.
Is Laser Hair Removal Safe?
Laser hair reduction has been used extensively and can be performed across a wide range of skin types when appropriate equipment and parameters are selected.
However, it is still an energy-based treatment and side effects can occur.
Common Temporary Reactions
- Redness around hair follicles
- Mild warmth or stinging
- Temporary perifollicular swelling
- Short-term skin sensitivity
Less Common Side Effects
- Burns or blisters
- Post-inflammatory hyperpigmentation
- Hypopigmentation
- Crusting
- Prolonged irritation
The risk is higher when the treatment parameters are unsuitable for the patient’s skin type, when recently tanned skin is treated, or when inadequate cooling or technique is used.
Who Should Be Assessed Before Treatment?
- People with active infection, wounds or inflammation in the treatment area
- People using medication that may increase photosensitivity
- Anyone who is recently tanned or sunburned
- People with a history of significant pigment changes or keloid scarring
- Patients with unusually rapid or excessive hair growth that may be hormonally driven
- Pregnant patients, as elective cosmetic laser procedures are generally deferred because safety data during pregnancy are limited
Laser Hair Removal vs IPL vs Shaving vs Waxing
| Method | How It Works | Typical Result |
|---|---|---|
| Laser Hair Removal | Uses a specific laser wavelength to target melanin in the hair follicle | Long-term reduction in hair growth after repeated sessions |
| IPL | Uses broad-spectrum intense pulsed light | Can reduce hair but is not a single-wavelength laser |
| Shaving | Cuts hair at the skin surface | Temporary; hair regrows relatively quickly |
| Waxing / Plucking | Pulls hair out of the follicle | Temporary and requires repeat treatment; may contribute to irritation or ingrown hairs |
How Much Does Laser Hair Removal Cost in Bangkok?
The cost depends mainly on the size of the treatment area and whether you book a single session or a treatment course.
Current Smooth Clinic laser hair removal prices include:
| Treatment Area | 1 Session | 5 Sessions |
|---|---|---|
| Mustache or Chin | 990 THB | 4,000 THB |
| Underarms | 990 THB | 4,000 THB |
| Full Arms | 2,599 THB | 11,000 THB |
| Full Legs | 4,500 THB | 20,000 THB |
| Bikini | 1,499 THB | 6,000 THB |
| Brazilian | 2,599 THB | 11,000 THB |
Prices and promotions may change. Please check the latest clinic pricing before treatment.
You can view more treatment areas and current prices on the Smooth Clinic Price List.
Why Choose Smooth Clinic for Laser Hair Removal in Bangkok?
- Primelase Excellence – A multi-wavelength laser platform designed for professional hair-reduction treatments.
- Individual Treatment Settings – Parameters are adjusted according to skin phototype, hair type and treatment area.
- Contact Cooling – Helps manage skin temperature and treatment comfort.
- Multiple Treatment Areas – From small areas such as underarms and facial hair to larger areas such as full legs and the back.
- Pre- and Post-Treatment Guidance – Instructions are provided to help reduce irritation and pigment-related complications.
Smooth Clinic is located in Asoke, Bangkok, near BTS Asok and MRT Sukhumvit.
Call: 088-121-8888
LINE OA: @smoothclinic
Conclusion
Laser hair removal is designed to provide long-term reduction in unwanted hair growth by targeting melanin within the hair and hair follicle.
Results depend on more than the power of the laser alone. A suitable treatment plan considers skin phototype, hair colour, hair thickness, wavelength, fluence, pulse duration and cooling.
Multiple sessions are usually required because hair follicles pass through different growth phases, and some patients may benefit from occasional maintenance treatments in the future.
Laser Hair Removal FAQs
Is Laser Hair Removal Permanent?
The more accurate term is permanent hair reduction. Laser can produce a long-term, stable reduction in regrowing hair, but it does not guarantee that every hair will disappear permanently for life.
How Many Laser Hair Removal Sessions Do I Need?
Many patients require around six or more sessions, but the number varies depending on the area, hair characteristics, skin type, hormones and response to treatment.
How Often Should I Have Laser Hair Removal?
Sessions may initially be scheduled around 4–6 weeks apart, although the interval should be adjusted according to the treatment area and hair growth cycle.
Will Hair Grow Back Thicker After Laser?
The intended effect is a reduction in hair density and thickness. Unusual paradoxical hair growth has been reported but is uncommon and should be assessed if increased hair growth occurs after treatment.
Does Laser Work on Fine Hair?
Fine hair may respond if it contains enough melanin, but white, grey, very light blonde and some red hairs usually respond poorly because they contain relatively little pigment.
Is Laser Hair Removal Safe for Dark Skin?
Yes, when appropriate wavelengths and treatment parameters are used. Darker skin contains more epidermal melanin, so careful settings and cooling are particularly important to reduce the risk of burns and pigment changes.
Can Laser Hair Removal Help Ingrown Hairs?
Yes, when ingrown hairs are caused by shaving or hairs growing back into the skin. Reducing hair density can help reduce recurrent razor bumps and pseudofolliculitis barbae.
What Is the Difference Between Laser and IPL?
Laser devices use specific wavelengths of light, while IPL uses a broader spectrum of intense pulsed light. Both can be used for hair reduction, but their energy delivery and treatment characteristics are different.
Should I Shave Before Laser Hair Removal?
Shaving is usually allowed and may be recommended before treatment. Plucking and waxing should generally be avoided because they remove the hair follicle target needed for laser treatment.
Can I Go in the Sun After Laser Hair Removal?
Limit strong sun exposure while the skin remains sensitive and use broad-spectrum sunscreen on exposed treatment areas to reduce the risk of pigment changes.
How Much Is Underarm Laser Hair Removal in Bangkok?
Smooth Clinic currently lists underarm laser hair removal at 990 THB for one session and 4,000 THB for five sessions. Prices and promotions may change, so check the latest price list before booking.
References
- American Academy of Dermatology (AAD). Laser Hair Removal: Overview.
- U.S. Food and Drug Administration (FDA). Primelase Excellence 510(k) Summary – K201594.
- Primelase Excellence. Primelase Excellence Handpieces and Wavelength Technology.
- Gan SD, Graber EM. Laser Hair Removal: A Review. Dermatologic Surgery. 2013;39(6):823-838.
- Dorgham NA, Dorgham DA. Lasers for Reduction of Unwanted Hair in Skin of Colour: A Systematic Review and Meta-analysis. Journal of the European Academy of Dermatology and Venereology. 2020;34(5):948-955.
- Battle EF. Advances in Laser Hair Removal in Skin of Color. Journal of Drugs in Dermatology. 2011;10(11):1235-1239.
- Laser and Light Treatments for Hair Reduction in Fitzpatrick Skin Types IV–VI. A Comprehensive Review of the Literature.