What Is IPL Hair Removal Technique?

IPL (Intense Pulse Light) removes hair by exposing hair follicles to high intensity light (not lasers).  The more pigment in the follicle, the more light it absorbs and the more heat goes into the follicle.  If it gets hot enough, the follicle eventually (after several treatments) dies, causing hair to grow no more.

IPL treatment is generally very quick, can lead to permanent hair removal, and is almost painfree (there can be an uncomfortable sensation of heat).

The number and frequency of treatments required to remove all hairs varies with the size of the area, the density of hairs and their colour.  Initially the hair may turn lighter and thinner in the treated area, before the follicles give up completely.  Also, only hairs in their growing phase (anaphase) are affected.  This is about a third of hairs at any one time.  

IPL works best on dark hairs on light-skinned people.  It runs the risk of causing temporary skin discoloration in non-white people, and it is largely ineffective against white hair.  IPL is also very expensive compared to most other hair removal techniques, and is not widely available.  People with sensitive skin may find it exacerbates existing skin conditions (like eczema).