Laser hair removal

Laser hair removal - more accurately described as laser hair reduction - uses light energy to damage hair follicles so they produce less hair, or no hair, over time. This page explains the technology, what determines whether it will work for you, and what the risks are.

The physics, briefly

The treatment relies on selective photothermolysis: choosing a wavelength of light, a pulse duration and an energy level such that the light is absorbed mainly by the target - melanin in the hair shaft - and converted to heat, damaging the follicle while leaving surrounding tissue as intact as possible.

Three variables are set for each patient and area:

• Wavelength determines how deep the light penetrates and how strongly it is absorbed by melanin. Shorter wavelengths are absorbed more strongly by melanin but penetrate less deeply and carry more risk in darker skin; longer wavelengths penetrate deeper and are absorbed less by skin melanin, which is why longer-wavelength devices are generally preferred for darker skin types.
• Pulse duration is matched to the size of the target. A longer pulse heats a larger structure like a thick follicle while giving the smaller structures of the epidermis time to cool.
• Fluence - the energy delivered - is set high enough to damage the follicle but low enough to avoid burning the skin. This is the trade-off at the centre of the treatment.

The skin is usually cooled during treatment to protect the epidermis.

Laser and IPL are not the same thing

It is worth knowing the difference, because the terms are often used interchangeably in advertising.

• A laser emits a single, specific wavelength of light. That precision is what allows the settings above to be tuned to the target.
• IPL (intense pulsed light) is not a laser. It emits a broad spectrum of wavelengths, filtered to a range. It can produce hair reduction, but the energy is spread across wavelengths rather than concentrated at the most useful one.

In practice, lasers are generally more effective per session for hair reduction and are usually preferred for darker skin types, where the precision matters most for safety. Which device is appropriate for you is determined at assessment.

Whether it will work for you

The single strongest predictor is the contrast between hair colour and skin colour.

• Dark, coarse hair responds best - it holds the most melanin.
• Grey, white and red hair, and very fine blonde hair, hold little or no melanin. There is no target for the laser to reach, and these hairs generally do not respond. No device or number of sessions overcomes this.
• Darker skin can be treated safely with appropriate wavelength and settings, but the margin between an effective treatment and a burn is narrower, so device selection and operator experience matter more.
• Tanned skin, including from fake tan, temporarily behaves like darker skin and increases the risk of burns and pigment change. Treatment is generally deferred.

An honest assessment includes being told when the treatment is unlikely to work for your hair.

Why multiple sessions are needed

Hair follicles cycle through three phases: growth (anagen), transition (catagen) and rest (telogen). Only follicles in the growth phase can be effectively damaged, because only then is the pigmented hair shaft connected to the structures that need to be reached.

At any moment, only a fraction of the follicles in an area are in the growth phase, and that fraction differs by body region. A course of treatments spaced weeks apart catches successive waves of follicles as they enter the growth phase. Missing or delaying sessions means missing those waves.

Expect a course of several sessions, with maintenance treatments likely at intervals afterwards. The number depends on the area, hair characteristics and how you respond.

What to expect

Before: a patch test at a first appointment; shaving the area rather than waxing, plucking, threading or using depilatory creams for the weeks beforehand (those methods remove the target the laser needs); avoiding sun exposure, solariums and fake tan; disclosing all medications, since some increase photosensitivity.

During: protective eyewear is worn by everyone in the room. The sensation is commonly described as a hot snap against the skin. Treatment time depends on the size of the area.

Immediately after: redness and raised bumps around the follicles are expected and usually settle within hours to a couple of days. Cooling can help.

Over the following weeks: treated hairs are pushed out and shed over roughly one to three weeks. This shedding is often mistaken for regrowth. Avoid hot showers, saunas, spas, swimming pools and strenuous exercise for a short period, keep the area clean, and use sun protection on treated skin.

Risks and side effects

• Redness, swelling and discomfort during and after treatment
• Blistering and burns
• Hyperpigmentation (darkening) and hypopigmentation (lightening) of the treated skin, which may be temporary or persist
• Scarring, including in people prone to keloid scarring
• Crusting or scabbing
• Folliculitis - inflammation or infection of treated follicles
• Reactivation of cold sores when treating near the mouth in people who carry the virus
• Paradoxical hypertrichosis - an increase in hair growth in or near the treated area, uncommon but recognised
• Eye injury without proper protective eyewear
• Little or no result, particularly with light or fine hair

Risk is higher in darker and in recently tanned skin, and where inappropriate settings are used.

Who should not be treated, or should wait

Treatment is generally deferred or avoided where there is active infection or broken skin in the area, recent sun exposure or tanning, current use of photosensitising medication, certain photosensitive conditions, or during pregnancy. A suspicious mole or lesion in the area should be assessed before any laser treatment - see mole removal and skin checks.

Where hair growth has increased markedly or suddenly, an underlying hormonal cause such as polycystic ovary syndrome should be considered and assessed medically rather than treating the hair alone.

Booking and costs

Costs depend on the area treated and the number of sessions in the course. A skin assessment with a nurse or aesthetician is $50 and is redeemable on products or services; a consultation with a Cosmetic Doctor is $150. Prices are as at September 2024 and include GST.

Me Clinic is at 4 Burke Road, Malvern East VIC 3145, a five minute walk from Caulfield station. The clinic is open Monday, Wednesday and Friday 9am to 5pm, Tuesday and Thursday 9am to 7pm, and Saturday 9am to 2pm.

Related pages

See body hair removal, facial hair removal, skin treatments, or all body procedures.

Individual results may vary. Any surgical or invasive procedure carries risks. Before proceeding you should seek a second opinion from an appropriately qualified health practitioner.