Page 52 - Mike Murphy's Blog Posts

A16 - The Hair Growth Cycle & Laser/IPL Treatments. When is the 'best' time to treat?
Hair grows in a well-known cycle - anagen, catagen and telogen.
The 'active' growing phase is anagen - during this phase the hair follicle will begin to grow from a single stem cell. The duration of this phase depends on the body location and can range from a few weeks to several years!
However, these phases 'overlap' in any particular skin area. In other words, when we look at the skin, we see hairs in all phases, at all times! It is quite difficult to see which hair is in which phase. This poses problems for laser/IPL hair removal operators.
The following image shows how these phases may be arranged for hair on the legs, upper lip, eyebrows and arms. As you can see, there really is a wide variation in all phases, except catagen.
In most hairs, the catagen phase lasts for only two to three weeks. During this stage the hair shaft detaches from the root and 'rises' up through the follicle awards the surface. This is often referred to as the 'transition' phase and the hair is known as a 'club' hair at this time.
The telogen phase is the 'resting' stage where all growth activity has stopped. Hairs usually shed during this phase - typically up to around 100 per day.
Once the follicle goes back into the anagen phase, the newly growing hair will 'push' out the club hair and replace it.
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