Nd:YAG and Alexandrite lasers for hair removal
Laser hair removal can reduce unwanted hair on the face and body by directing concentrated light into the pigment within the hair follicle. The absorbed energy becomes heat, damaging the follicle’s growth mechanism while leaving the surrounding skin largely unaffected. Several treatment sessions are usually required because hair responds best during its active growth phase.
The two technologies most often compared are the Alexandrite laser and the Nd:YAG laser. Both can provide long-term hair reduction, but they differ in wavelength, depth of penetration, skin suitability, comfort, and effectiveness for particular hair types.
Choosing between them should involve more than comparing brand names or treatment prices. A trained practitioner needs to assess skin tone, tanning, hair colour, hair thickness, treatment area, medical history, and the likelihood of pigment changes. This assessment is especially important in South Africa, where patients may have a wide range of skin tones and regular exposure to strong sunlight.
How the two laser types work
Alexandrite lasers emit light at a wavelength of 755 nanometres. This wavelength is strongly absorbed by melanin, the pigment responsible for colour in both the hair and the skin. Because the laser is highly attracted to pigment, it can heat the hair follicle efficiently when there is a clear contrast between darker hair and lighter skin.
Nd:YAG lasers use a longer wavelength of 1064 nanometres. The light penetrates more deeply and is absorbed less by the melanin in the surface layers of the skin. This makes Nd:YAG a commonly selected option for darker skin tones, although correct settings, cooling, and clinical experience remain essential.
Neither laser removes every hair permanently after a single appointment. Hair grows in cycles, and only follicles in the active anagen phase are particularly responsive. A planned course of treatments can produce significant, lasting reduction, while occasional maintenance appointments may be needed as new growth appears.
Alexandrite laser strengths and limitations
Alexandrite treatment is often highly effective for people with fair to light-olive skin and coarse, dark hair. Its strong melanin absorption can deliver rapid heating of the follicle, and many patients notice a reduction in density after the first few sessions. It is frequently used on the legs, underarms, bikini area, back, and other larger body regions.
The same pigment attraction that makes Alexandrite effective can create a greater risk of burns or post-inflammatory hyperpigmentation when used on recently tanned or naturally darker skin. Settings must be carefully adjusted, and a practitioner may recommend an alternative wavelength when there is limited contrast between the hair and the skin.
Alexandrite is less useful for white, grey, and very pale blonde hair because these colours contain little melanin for the laser to target. Fine hair can also be more difficult to treat than thick hair. A consultation helps establish whether the expected benefit justifies treatment and whether another hair-removal method may be more appropriate for certain areas.
Nd:YAG laser strengths and limitations
Nd:YAG is valued for its comparatively lower absorption in epidermal melanin. It can therefore be a safer choice for medium, deep, or recently darker skin types when performed by an experienced medical aesthetic team. The longer wavelength reaches deeper follicles and may be particularly useful for coarse hair on areas such as the back, chest, legs, and face.
Because Nd:YAG interacts less strongly with pigment, it may feel less immediately powerful on some hair types than Alexandrite. It can require carefully selected energy levels and a full course of appointments to achieve satisfactory reduction. Fine or lightly pigmented hair may respond slowly, and very pale hair is generally unsuitable for both technologies.
Treatment comfort varies according to the body area, hair density, device, and individual sensitivity. Modern systems often use contact cooling, chilled air, or another cooling method to protect the skin and make each pulse more comfortable. A warm snapping sensation is common, while persistent severe pain should be reported during the appointment.
| Feature | Alexandrite laser | Nd:YAG laser |
|---|---|---|
| Wavelength | 755 nm | 1064 nm |
| Main advantage | Strong absorption by hair pigment and fast treatment of suitable areas | Deeper penetration with lower absorption by surface skin pigment |
| Often suitable for | Fair to light-olive skin with dark, coarse hair | Medium to deep skin tones, including many darker skin types |
| Hair response | Often excellent for dark, coarse hair with good skin-hair contrast | Useful for coarse dark hair, though fine hair may respond less readily |
| Main concern | Greater pigment-change risk on darker or tanned skin if settings are unsuitable | May need careful energy selection and several sessions |
| Effect on pale hair | Limited for blonde, grey, or white hair | Limited for blonde, grey, or white hair |
| Essential safeguards | Skin assessment, cooling, sun avoidance, and patch testing where appropriate | Experienced operator, suitable fluence, cooling, and careful monitoring |
Matching the laser to your skin and hair
Skin tone is one of the most important factors in laser selection, but it is not the only one. A practitioner will also consider whether the skin is tanned, whether the hair is coarse or fine, and whether the area has previously developed dark marks, irritation, or scarring after injury. Facial hair may require additional discussion because hormonal changes can influence regrowth.
A darker skin tone does not automatically rule out Alexandrite, and lighter skin does not automatically make it the best choice. Some modern platforms allow practitioners to adjust pulse duration, fluence, spot size, and cooling. Even so, Nd:YAG may offer a more suitable safety profile when there is substantial epidermal melanin.
Sun exposure deserves particular attention in the South African climate. Tanned skin contains more active pigment at the surface, which can increase the chance of discomfort and pigment alteration. Patients can review this South African climate guidance when planning treatment around holidays, outdoor activities, and seasonal changes.
Preparing for treatment safely
Patients are generally advised to avoid waxing, tweezing, or epilating for several weeks before laser hair removal because these methods remove the follicle that the laser needs to target. Shaving is usually acceptable and may be recommended shortly before the appointment. The treatment area should be clean and free from creams, oils, deodorant, and cosmetic products unless the clinic provides different instructions.
Sun protection is central before and after every session. Broad-spectrum sunscreen, protective clothing, shade, and sensible scheduling can help minimise tanning and reduce the risk of post-treatment pigment changes. A consistent sunscreen routine is particularly important when treating exposed areas such as the face, neck, arms, and lower legs.
A consultation should cover active skin conditions, cold sores, medications that increase light sensitivity, recent tanning, pregnancy, hormonal concerns, and previous reactions to cosmetic procedures. The clinic may recommend a small test area before treating a larger region. This provides useful information about the skin’s response without exposing the entire area at once.
What results and aftercare may involve
Immediately after treatment, the skin can look pink or slightly swollen around the follicles. This follicular response is common and usually settles within a short period. Cool compresses, gentle cleansing, and a bland moisturiser may help, while hot baths, intense exercise, friction, and fragranced products may need to be avoided temporarily.
Treated hairs do not always fall out immediately. They may appear to continue growing before being shed over the following days or weeks. Appointments are commonly spaced several weeks apart, depending on the body area and the patient’s growth cycle. Facial hair often follows a different schedule from leg or body hair.
Results vary because hormonal conditions, medication, hair colour, genetics, and treatment consistency all influence regrowth. Laser hair removal is best described as long-term hair reduction rather than a guaranteed permanent removal of every follicle. New or dormant growth may require maintenance treatment over time.
Practical steps for choosing a treatment
The most reliable way to select a wavelength is to combine professional skin assessment with realistic expectations about hair reduction. Consider these practical points before booking:
- Arrange a consultation with a qualified practitioner who routinely treats a broad range of South African skin tones.
- Ask which wavelength is recommended for your current skin tone, natural hair colour, hair thickness, and treatment area.
- Disclose recent tanning, medications, hormonal conditions, previous pigment changes, and any history of cold sores.
- Follow the clinic’s shaving, sun protection, skincare, and aftercare instructions precisely.
- Discuss expected session numbers, maintenance appointments, possible side effects, and the plan if the initial response is limited.
A reputable clinic should explain why a particular laser is being selected rather than presenting one device as universally superior. The safest and most effective option may differ between body areas on the same patient, especially when facial hair is finer or the skin is more exposed to sunlight.
Book a professional assessment with Laserderm to compare Nd:YAG and Alexandrite treatment options for your skin and hair profile. A personalised plan can help you pursue smoother skin with appropriate settings, realistic expectations, and medically guided care.