Is my treatment working?: The Power of the 1 cm Rule

How do I know if my treatment is working ?

So you've started a new treatment and you're wondering if it's helping your hair. How do you know?

Well, it's important first figure out the answer the following questions:

What type of hair loss do I have? Am I supposed to get more hair with my treatment? ....or is the purpose of the treatment to STOP further loss?

For many types of hair loss, the goal of treatment is to stimulate new hair growth. Because hair only can grow about 1 cm per month maximum - one would expect a number of 1 cm hairs after the first month of treatment and a number of 2 cm hairs after two months. Generally when I invite patients to meet with me at 6 months - I expect to see a number of 6 cm hairs.  I like to call this the "1 cm rule of hair regrowth"

However, sometimes treatment is designed to thicken existing hairs and improve quality rather than trigger new sprouts of hair. So the main factor to assess in this case is hair density - and improvement in overall scalp coverage. Careful assessment for 1 cm, 2 cm and 6 cm hairs is less important in these cases.

For some types of hair loss, particularly the group of conditions known as scarring hair loss conditions, the primary goal of treatment is to stop the hair loss - not to regrow hair. Therefore, if a patient looks the exact same in 6 months, the treatment is rated as a success.