Unwanted underarm hair has always been a concern, especially among ladies. Apart from the age-old methods of shaving, trimming, waxing, plucking and application of depilatory creams, which are largely temporary measures, the main treatment focus nowadays is on semi-permanent hair removal with light-based devices. Temporary hair removal methods remove the visible hair shaft, but leaves the hair follicles and hair roots intact. Semi-permanent hair removal methods destroys the hair follicles and hair roots, thus reducing the hair growth.
Let's focus on the semi-permanent methods:
Both IPL and laser hair removal work on the same principle. They emit light energy, which is absorbed by the pigmentation in hair, causing it to heat up and damaging or destroying the hair follicle. The difference between the two, is the type of light energy used. IPL utilizes a source of broad-spectrum visible light, which is then controlled by filters to remove the unsuitable wavelengths, leaving wavelengths that target the melanin pigment present in hair. Lasers, on the other hand, emit a single wavelength of light energy targeted at melanin. This energy is thus more focused and precise, without causing damage to surrounding tissues.
Bombarded with constant advertisements of cheaply priced IPL hair removal, it does seem tempting to many. True, IPL hair removal does work for many, but for a few, it may not be the ideal treatment. The utmost important factor to consider when deciding between which light-based treatments to choose from, is safety. If you are of a darker skin type, laser hair removal is safe than IPL. There are also various laser systems used for hair removal. In our local context, the long-pulsed Nd:YAG (1064nm wavelength) is a safe choice, even for darker skin types. Mild side effects can still occur, such as swelling and hyperpigmentation; but still definitely safer than using IPL, which can result in burns.
The secondary concerns when deciding between IPL and laser hair removal would then be the number of sessions needed. Because of the higher energy and more focused treatment of laser hair removal machines, the number of sessions needed are fewer. For underarms, 4-6 sessions of laser hair removal treatments can achieve ideal results. IPL, on the other hand, can achieve beneficial results, but in a larger number of sessions. This may be an important factor for those with busy schedules.
With either IPL or laser hair removal treatments, the treated area may not be completely devoid of hair. Any remaining hairs are usually sparse, lighter in colour and finer in texture. This usually doesn't bother most of my patients any more, but some still do return intermittently for treatment of those few residual hairs.
Hope I have helped to shed some light in your decision-making process.