Telogen Effluvium Hair Loss
What is Telogen Effluvium Hair Loss?
On average, about 85% to 90% of the hairs on the head of a person are actively growing (anagen phase) while other hair follicles rest (telogen phase). A hair stays in the anagen phase for 2-4 years, then enters the telogen phase and rests for about 2-4 months and sheds. In the problem of hair loss, new growing hair replaces the shedding hair. The average person naturally loses about 100 hairs a day. In a person with telogen effluvium, some body changes or shocks push more hair into the telogen phase. Typically in this situation, about 30% of the hairs stop growing and go into a resting phase before shedding. So if you have telogen effluvium, you can lose an average of 300 hairs a day instead of 100.
Telogen effluvium can be triggered by a number of different events, including:
- Major physical trauma
- Great psychological stress
- High fever, severe infection or other illnesses
- Excessive weight loss
- Excessive change in diet
- Sudden hormonal changes, including those associated with childbirth and menopause
- iron deficiency
- Hypothyroidism or hyperthyroidism
Since some medicines stay in place for 2-4 months before the hairs in the telogen phase are shed, you may not notice hair loss until 2-4 months before the event causing the problem.
Although losing a lot of hair in a short period of time can be scary, the condition is usually temporary. Every hair that is pushed early into the telogen phase is replaced by a new, growing hair, so there is no danger of complete baldness. Because scalp hair grows slowly, your hair may feel thinner or appear thinner for a while, but the fullness returns as new hair grows.
What are the Symptoms of Telogen Effluvium Hair Loss?
If you have telogen effluvium, you will see more hair than usual on your pillowcase, shower, bathroom floor and hairbrush.
How Is Telogen Effluvium Hair Loss Diagnosed?
Most cases of telogen effluvium can be diagnosed based on a patient’s medical history, scalp and hair examination. If the hair loss has been occurring for several months, there may be a noticeable thinning, but often the hair loss may not be as intense as a doctor might notice.
Patients may be asked to collect all the hairs that grow out of the scalp over a 24-hour period and count them to see if the hair loss is really excessive. Losing less than 100 hairs a day is considered normal. In addition, you may be asked to collect and count the hair shed for 1-2 weeks to see when the shedding starts to decrease.
In some rare cases, if there is reason to doubt the diagnosis, a biopsy of the scalp may be performed. In this procedure, a small part of the scalp containing several hair follicles is removed and examined under a microscope.
Your doctor may also do blood tests to check for conditions such as thyroid abnormalities that can contribute to hair loss.